vllm_v0.7.2-dynemo-kv-disagg-patch.patch 160 KB
Newer Older
1
diff --git a/vllm/config.py b/vllm/config.py
ptarasiewiczNV's avatar
ptarasiewiczNV committed
2
index 9ba49757..a2f88854 100644
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
--- a/vllm/config.py
+++ b/vllm/config.py
@@ -2629,7 +2629,7 @@ class KVTransferConfig(BaseModel):
     kv_buffer_size: float = 1e9
 
     # Whether this vLLM instance produces, consumes KV cache, or both. Choices
-    # are 'kv_producer', 'kv_consumer', and 'both'.
+    # are 'kv_producer', 'kv_consumer', and 'kv_both'.
     kv_role: Optional[str] = None
 
     # The rank of this vLLM instance in the KV cache transfer. Typical value:
@@ -2647,6 +2647,14 @@ class KVTransferConfig(BaseModel):
     # The KV connector port, used to build distributed connection
     kv_port: int = 14579
 
+
+    # This does not need to be set by the user. It is set by the connector.
+    kv_producers_parallel_size: Optional[int] = None
+    kv_producers_tensor_parallel_size: Optional[int] = None
+    kv_producers_pipeline_parallel_size: Optional[int] = None
+    kv_consumers_tensor_parallel_size: Optional[int] = None
+    kv_consumers_pipeline_parallel_size: Optional[int] = None
+
     def compute_hash(self) -> str:
         """
         WARNING: Whenever a new field is added to this config,
ptarasiewiczNV's avatar
ptarasiewiczNV committed
29
30
31
32
33
@@ -2680,11 +2688,12 @@ class KVTransferConfig(BaseModel):
                 f"Supported roles are `kv_producer`, `kv_consumer`, "
                 f"and `kv_both`")
 
-        if self.kv_connector is not None and self.kv_role is None:
34
+        if self.kv_connector is not None and self.kv_connector != "DynemoNixlConnector" and self.kv_role is None:
ptarasiewiczNV's avatar
ptarasiewiczNV committed
35
             raise ValueError("Please specify kv_disagg_role when kv_connector "
36
37
38
39
40
41
42
                              "is set, supported roles are `kv_producer`, "
                              "`kv_consumer`, and `kv_both`")
 
+
     @property
     def is_kv_transfer_instance(self) -> bool:
         return self.kv_connector is not None and \
ptarasiewiczNV's avatar
ptarasiewiczNV committed
43
44
45
46
@@ -2694,6 +2703,8 @@ class KVTransferConfig(BaseModel):
     def need_kv_parallel_group(self) -> bool:
         # for those database-based connector, vLLM does not need to create
         # parallel group, and in that case the kv parallel size will be 1.
47
+        if self.kv_connector == "DynemoNixlConnector":
ptarasiewiczNV's avatar
ptarasiewiczNV committed
48
49
50
51
52
+            return False
         return self.kv_connector is not None and self.kv_parallel_size > 1
 
     @property
@@ -2706,6 +2717,18 @@ class KVTransferConfig(BaseModel):
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
         return self.kv_connector is not None and \
             self.kv_role in ["kv_consumer", "kv_both"]
 
+    @property
+    def tensor_parallel_multiplier(self) -> int:
+        return self.kv_consumers_tensor_parallel_size // self.kv_producers_tensor_parallel_size
+
+    @property
+    def kv_consumers_parallel_size(self) -> int:
+        return self.kv_parallel_size - self.kv_producers_parallel_size
+
+    @property
+    def kv_world_size(self) -> int:
+        return self.kv_producers_parallel_size + self.kv_consumers_parallel_size * self.tensor_parallel_multiplier
+
 
 class CompilationLevel:
     # constants for the levels of the compilation process
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
diff --git a/vllm/core/block/cpu_gpu_block_allocator.py b/vllm/core/block/cpu_gpu_block_allocator.py
index 359b5b26..d52ee050 100644
--- a/vllm/core/block/cpu_gpu_block_allocator.py
+++ b/vllm/core/block/cpu_gpu_block_allocator.py
@@ -6,6 +6,7 @@ from vllm.core.block.interfaces import (Block, BlockAllocator, BlockId,
                                         DeviceAwareBlockAllocator)
 from vllm.core.block.naive_block import NaiveBlock, NaiveBlockAllocator
 from vllm.core.block.prefix_caching_block import PrefixCachingBlockAllocator
+from vllm.core.event_manager import KVCacheEventManager
 from vllm.platforms import current_platform
 from vllm.utils import Device
 
@@ -28,6 +29,7 @@ class CpuGpuBlockAllocator(DeviceAwareBlockAllocator):
         num_gpu_blocks: int,
         num_cpu_blocks: int,
         block_size: int,
+        event_manager: Optional[KVCacheEventManager] = None,
     ) -> DeviceAwareBlockAllocator:
         """Creates a CpuGpuBlockAllocator instance with the specified
         configuration.
@@ -64,6 +66,7 @@ class CpuGpuBlockAllocator(DeviceAwareBlockAllocator):
         cpu_block_ids = block_ids[num_gpu_blocks:]
 
         if allocator_type == "naive":
+            assert event_manager is None, "Event API not supported with naive allocator."
             gpu_allocator: BlockAllocator = NaiveBlockAllocator(
                 create_block=NaiveBlock,  # type: ignore
                 num_blocks=num_gpu_blocks,
@@ -82,12 +85,14 @@ class CpuGpuBlockAllocator(DeviceAwareBlockAllocator):
                 num_blocks=num_gpu_blocks,
                 block_size=block_size,
                 block_ids=gpu_block_ids,
+                event_manager=event_manager,
             )
 
             cpu_allocator = PrefixCachingBlockAllocator(
                 num_blocks=num_cpu_blocks,
                 block_size=block_size,
                 block_ids=cpu_block_ids,
+                event_manager=event_manager,
             )
         else:
             raise ValueError(f"Unknown allocator type {allocator_type=}")
@@ -95,10 +100,12 @@ class CpuGpuBlockAllocator(DeviceAwareBlockAllocator):
         return CpuGpuBlockAllocator(
             cpu_block_allocator=cpu_allocator,
             gpu_block_allocator=gpu_allocator,
+            event_manager=event_manager,
         )
 
     def __init__(self, cpu_block_allocator: BlockAllocator,
-                 gpu_block_allocator: BlockAllocator):
+                 gpu_block_allocator: BlockAllocator,
+                 event_manager: Optional[KVCacheEventManager] = None,):
         assert not (
             cpu_block_allocator.all_block_ids
             & gpu_block_allocator.all_block_ids
@@ -108,6 +115,7 @@ class CpuGpuBlockAllocator(DeviceAwareBlockAllocator):
             Device.CPU: cpu_block_allocator,
             Device.GPU: gpu_block_allocator,
         }
+        self.event_manager = event_manager
 
         self._swap_mapping: Dict[int, int] = {}
         self._null_block: Optional[Block] = None
ptarasiewiczNV's avatar
ptarasiewiczNV committed
136
137
138
139
140
141
142
143
144
145
146
147
diff --git a/vllm/core/block/naive_block.py b/vllm/core/block/naive_block.py
index c388366b..c1883736 100644
--- a/vllm/core/block/naive_block.py
+++ b/vllm/core/block/naive_block.py
@@ -135,6 +135,7 @@ class NaiveBlockAllocator(BlockAllocator):
             raise BlockAllocator.NoFreeBlocksError()
 
         block_id = self._free_block_indices.popleft()
+        # TODO: figure out why sometime block_id is None
         self._refcounter.incr(block_id)
         return block_id
 
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
diff --git a/vllm/core/block/prefix_caching_block.py b/vllm/core/block/prefix_caching_block.py
index 1ca9e49d..b1591c0c 100644
--- a/vllm/core/block/prefix_caching_block.py
+++ b/vllm/core/block/prefix_caching_block.py
@@ -4,7 +4,7 @@ import sys
 from bisect import bisect_left
 from os.path import commonprefix
 from typing import (Callable, Dict, FrozenSet, Iterable, List, Optional, Set,
-                    Tuple)
+                    Tuple, TYPE_CHECKING)
 
 from vllm.core.block.common import (CacheMetricData, CopyOnWriteTracker,
                                     get_all_blocks_recursively)
@@ -23,6 +23,9 @@ PrefixHash = int
 # then we know this block hasn't been accessed yet.
 _DEFAULT_LAST_ACCESSED_TIME = -1
 
+if TYPE_CHECKING:
+    from vllm.core.event_manager import KVCacheEventManager
+
 logger = init_logger(__name__)
 
 
@@ -80,6 +83,7 @@ class PrefixCachingBlockAllocator(BlockAllocator):
         block_size: int,
         block_ids: Optional[Iterable[int]] = None,
         eviction_policy: EvictionPolicy = EvictionPolicy.LRU,
+        event_manager: Optional["KVCacheEventManager"] = None,
     ):
         if block_ids is None:
             block_ids = range(num_blocks)
@@ -131,6 +135,9 @@ class PrefixCachingBlockAllocator(BlockAllocator):
 
         self.metric_data = CacheMetricData()
 
+        self.event_manager = event_manager
+
+    # Implements Block.Factory.
     def _create_block(
         self,
         prev_block: Optional[Block],
@@ -337,6 +344,9 @@ class PrefixCachingBlockAllocator(BlockAllocator):
         assert self._refcounter.get(_block_id) == 0
         assert _block_id == block_id
 
+        if self.event_manager:
+            self.event_manager.enqueue_removed_event(content_hash_to_evict)
+
         self._cached_blocks.pop(content_hash_to_evict)
 
         self._refcounter.incr(block_id)
@@ -513,6 +523,10 @@ class PrefixCachingBlockAllocator(BlockAllocator):
             # Mark this block as touched so that it can be marked as
             # computed after the entire batch of sequences are scheduled.
             self._touched_blocks.add(block.block_id)
+
+            if self.event_manager:
+                self.event_manager.enqueue_stored_event(block.prev_block, block)
+
             return block.block_id
 
         # Reuse the cached content hash
diff --git a/vllm/core/block_manager.py b/vllm/core/block_manager.py
GuanLuo's avatar
GuanLuo committed
211
index c5b3b04f..c72001f7 100644
212
213
--- a/vllm/core/block_manager.py
+++ b/vllm/core/block_manager.py
GuanLuo's avatar
GuanLuo committed
214
@@ -10,7 +10,10 @@ from vllm.core.block.interfaces import Block
215
216
217
 from vllm.core.block.prefix_caching_block import (ComputedBlocksTracker,
                                                   LastAccessBlocksTracker)
 from vllm.core.block.utils import check_no_caching_or_swa_for_blockmgr_encdec
GuanLuo's avatar
GuanLuo committed
218
+from vllm.core.event_manager import KVCacheEventManager
219
 from vllm.core.interfaces import AllocStatus, BlockSpaceManager
GuanLuo's avatar
GuanLuo committed
220
221
+from vllm.envs import (VLLM_KV_CAPI_PATH, VLLM_KV_COMPONENT, VLLM_KV_NAMESPACE,
+                       VLLM_WORKER_ID)
222
223
224
 from vllm.sequence import Sequence, SequenceGroup, SequenceStatus
 from vllm.utils import Device
 
GuanLuo's avatar
GuanLuo committed
225
@@ -60,6 +63,7 @@ class SelfAttnBlockSpaceManager(BlockSpaceManager):
226
227
228
 
     def __init__(
         self,
GuanLuo's avatar
GuanLuo committed
229
+        model_name: str,
230
231
232
         block_size: int,
         num_gpu_blocks: int,
         num_cpu_blocks: int,
GuanLuo's avatar
GuanLuo committed
233
@@ -91,11 +95,28 @@ class SelfAttnBlockSpaceManager(BlockSpaceManager):
234
235
236
 
         self.watermark_blocks = int(watermark * num_gpu_blocks)
 
GuanLuo's avatar
GuanLuo committed
237
238
239
240
241
242
243
244
245
246
247
248
249
+        kv_event_manager_params = [
+            VLLM_WORKER_ID, VLLM_KV_CAPI_PATH, VLLM_KV_NAMESPACE,
+            VLLM_KV_COMPONENT
+        ]
+        set_kv_event_manager_params = len(
+            [param for param in kv_event_manager_params if param is not None])
+
+        if set_kv_event_manager_params == len(kv_event_manager_params):
+            self.event_manager = KVCacheEventManager(
+                namespace=VLLM_KV_NAMESPACE,
+                component=VLLM_KV_COMPONENT,
+                worker_id=VLLM_WORKER_ID,
+                lib_path=VLLM_KV_CAPI_PATH)
250
251
252
253
254
255
256
257
258
259
260
261
262
263
+        else:
+            self.event_manager = None
+
         self.block_allocator = CpuGpuBlockAllocator.create(
             allocator_type="prefix_caching" if enable_caching else "naive",
             num_gpu_blocks=num_gpu_blocks,
             num_cpu_blocks=num_cpu_blocks,
             block_size=block_size,
+            event_manager=self.event_manager,
         )
 
         self.block_tables: Dict[SeqId, BlockTable] = {}
diff --git a/vllm/core/event_manager.py b/vllm/core/event_manager.py
new file mode 100644
GuanLuo's avatar
GuanLuo committed
264
index 00000000..350453cd
265
266
--- /dev/null
+++ b/vllm/core/event_manager.py
GuanLuo's avatar
GuanLuo committed
267
268
@@ -0,0 +1,102 @@
+# SPDX-License-Identifier: Apache-2.0
269
+import ctypes
GuanLuo's avatar
GuanLuo committed
270
+import logging
271
+import uuid
GuanLuo's avatar
GuanLuo committed
272
273
274
275
+from ctypes import c_char_p, c_size_t, c_uint32, c_void_p, c_int64
+from typing import Optional
+
+from vllm.core.block.prefix_caching_block import PrefixCachingBlock, PrefixHash
276
277
278
+
+logger = logging.getLogger(__name__)
+
GuanLuo's avatar
GuanLuo committed
279
+
280
+class DynemoResult:
281
282
283
+    OK = 0
+    ERR = 1
+
GuanLuo's avatar
GuanLuo committed
284
+
285
+class KVCacheEventManager:
GuanLuo's avatar
GuanLuo committed
286
287
288
+
+    def __init__(self, namespace: str, component: str, worker_id: int,
+                 lib_path: str):
289
290
291
292
+        self.lib = None
+
+        try:
+            self.lib = ctypes.CDLL(lib_path)
293
294
+            self.lib.dynemo_llm_init.argtypes = [c_char_p, c_char_p, c_int64]
+            self.lib.dynemo_llm_init.restype = c_uint32
295
+
296
+            result = self.lib.dynemo_llm_init(namespace.encode(),
GuanLuo's avatar
GuanLuo committed
297
+                                              component.encode(), worker_id)
298
+            if result == DynemoResult.OK:
GuanLuo's avatar
GuanLuo committed
299
300
301
+                logger.info(
+                    "KVCacheEventManager initialized successfully. Ready to publish KV Cache Events"
+                )
302
303
304
305
306
307
+            else:
+                logger.info("KVCacheEventManager initialization failed!")
+
+        except Exception as e:
+            print(f"Failed to load {lib_path}")
+            raise e
GuanLuo's avatar
GuanLuo committed
308
+
309
+        self.lib.dynemo_kv_event_publish_stored.argtypes = [
GuanLuo's avatar
GuanLuo committed
310
311
312
313
314
315
316
+            ctypes.c_uint64,  # event_id
+            ctypes.POINTER(ctypes.c_uint32),  # token_ids
+            ctypes.POINTER(ctypes.c_size_t),  # num_block_tokens
+            ctypes.POINTER(ctypes.c_uint64),  # block_ids
+            ctypes.c_size_t,  # num_blocks
+            ctypes.POINTER(ctypes.c_uint64),  # parent_hash
+            ctypes.c_uint64,  # lora_id
317
+        ]
318
+        self.lib.dynemo_kv_event_publish_stored.restype = ctypes.c_uint32  # dynemo_llm_result_t
319
+
320
+        self.lib.dynemo_kv_event_publish_removed.argtypes = [
GuanLuo's avatar
GuanLuo committed
321
322
323
+            ctypes.c_uint64,  # event_id
+            ctypes.POINTER(ctypes.c_uint64),  # block_ids
+            ctypes.c_size_t,  # num_blocks
324
+        ]
325
+        self.lib.dynemo_kv_event_publish_removed.restype = ctypes.c_uint32  # dynemo_llm_result_t
326
327
328
+
+        self.event_id_counter = 0
+
GuanLuo's avatar
GuanLuo committed
329
330
331
332
+    def enqueue_stored_event(self, parent: Optional[PrefixCachingBlock],
+                             block: PrefixCachingBlock):
+        token_ids_arr = (ctypes.c_uint32 *
+                         len(block.token_ids))(*block.token_ids)
333
334
+        num_block_tokens = (ctypes.c_size_t * 1)(len(block.token_ids))
+        block_hash = (ctypes.c_uint64 * 1)(block.content_hash)
GuanLuo's avatar
GuanLuo committed
335
336
+        parent_hash = ((ctypes.c_uint64 * 1)(parent.content_hash)
+                       if parent is not None else None)
337
338
+
+        # Publish the event
339
+        result = self.lib.dynemo_kv_event_publish_stored(
GuanLuo's avatar
GuanLuo committed
340
341
342
343
344
345
346
+            self.event_id_counter,  # uint64_t event_id
+            token_ids_arr,  # const uint32_t *token_ids
+            num_block_tokens,  # const uintptr_t *num_block_tokens
+            block_hash,  # const uint64_t *block_ids
+            1,  # uintptr_t num_blocks
+            parent_hash,  # const uint64_t *parent_hash
+            0,  # uint64_t lora_id
347
348
+        )
+
349
+        if result == DynemoResult.OK:
350
351
+            logger.debug(f"Store - Published KV Event: {block.content_hash}")
+        else:
GuanLuo's avatar
GuanLuo committed
352
353
+            logger.debug(
+                f"Store - Failed to Publish KV Event: {block.content_hash}")
354
355
356
357
+
+        self.event_id_counter += 1
+
+    def enqueue_removed_event(self, block_hash: PrefixHash):
358
+        result = self.lib.dynemo_kv_event_publish_removed(
359
360
+            self.event_id_counter,
+            (ctypes.c_uint64 * 1)(block_hash),
GuanLuo's avatar
GuanLuo committed
361
362
363
+            1,
+        )
+
364
+        if result == DynemoResult.OK:
365
366
367
368
369
370
+            logger.debug(f"Remove - Published KV Event: {block_hash}")
+        else:
+            logger.debug(f"Remove - Failed to Publish KV Event: {block_hash}")
+
+        self.event_id_counter += 1
diff --git a/vllm/core/scheduler.py b/vllm/core/scheduler.py
371
index f507847a..ee20d50c 100644
372
373
--- a/vllm/core/scheduler.py
+++ b/vllm/core/scheduler.py
374
@@ -8,18 +8,17 @@ from collections import deque
ptarasiewiczNV's avatar
ptarasiewiczNV committed
375
376
 from dataclasses import dataclass, field
 from typing import Callable, Deque, Dict, Iterable, List, Optional
377
 from typing import Sequence as GenericSequence
ptarasiewiczNV's avatar
ptarasiewiczNV committed
378
379
-from typing import Set, Tuple, Union
+from typing import Set, Tuple, Union, Any
380
381
382
383
384
385
 
-from vllm.config import CacheConfig, LoRAConfig, SchedulerConfig
+from vllm.config import ModelConfig, CacheConfig, LoRAConfig, SchedulerConfig
 from vllm.core.interfaces import AllocStatus, BlockSpaceManager
 from vllm.logger import init_logger
 from vllm.lora.request import LoRARequest
ptarasiewiczNV's avatar
ptarasiewiczNV committed
386
387
388
389
390
391
392
393
394
395
 from vllm.prompt_adapter.request import PromptAdapterRequest
 from vllm.sequence import (Sequence, SequenceData, SequenceGroup,
                            SequenceGroupMetadata, SequenceGroupMetadataDelta,
-                           SequenceStatus)
+                           SequenceStatus, SequenceStage)
 from vllm.utils import Device, PyObjectCache
-
 logger = init_logger(__name__)
 
 # Test-only. If configured, decode is preempted with
396
@@ -325,12 +324,14 @@ class Scheduler:
397
398
399
400
401
402
403
404
405
406
407
408
409
410
 
     def __init__(
         self,
+        model_config: ModelConfig,
         scheduler_config: SchedulerConfig,
         cache_config: CacheConfig,
         lora_config: Optional[LoRAConfig],
         pipeline_parallel_size: int = 1,
         output_proc_callback: Optional[Callable] = None,
     ) -> None:
+        self.model_config = model_config
         self.scheduler_config = scheduler_config
         self.cache_config = cache_config
         # Note for LoRA scheduling: the current policy is extremely
411
@@ -356,6 +357,7 @@ class Scheduler:
412
413
414
415
416
417
418
 
         # Create the block space manager.
         self.block_manager = BlockSpaceManagerImpl(
+            model_name=self.model_config.served_model_name,
             block_size=self.cache_config.block_size,
             num_gpu_blocks=num_gpu_blocks,
             num_cpu_blocks=num_cpu_blocks,
419
@@ -371,6 +373,14 @@ class Scheduler:
ptarasiewiczNV's avatar
ptarasiewiczNV committed
420
421
422
423
424
425
426
427
428
429
430
431
432
433
         # Sequence groups in the SWAPPED state.
         # Contain decode requests that are swapped out.
         self.swapped: Deque[SequenceGroup] = deque()
+
+        # Sequence groups in the REMOTE_PREFILLING state.
+        # Contain requests that are being prefilled by a remote worker.
+        self.remote_prefilling: Deque[SequenceGroup] = deque()
+
+        self._remote_prefill_outputs: Dict[str, int] = {}
+
+
         # Sequence groups finished requests ids since last step iteration.
         # It lets the model know that any state associated with these requests
         # can and must be released after the current step.
434
@@ -501,7 +511,7 @@ class Scheduler:
ptarasiewiczNV's avatar
ptarasiewiczNV committed
435
436
437
438
 
     def has_unfinished_seqs(self) -> bool:
         return len(self.waiting) != 0 or len(self.running) != 0 or len(
-            self.swapped) != 0
439
+            self.swapped) != 0 or len(self.remote_prefilling) != 0
ptarasiewiczNV's avatar
ptarasiewiczNV committed
440
441
442
 
     def get_prefix_cache_hit_rate(self, device: Device) -> float:
         return self.block_manager.get_prefix_cache_hit_rate(device)
443
@@ -523,6 +533,7 @@ class Scheduler:
ptarasiewiczNV's avatar
ptarasiewiczNV committed
444
445
446
         budget: SchedulingBudget,
         curr_loras: Optional[Set[int]],
         enable_chunking: bool = False,
447
+        finished_prefills: Optional[Set[str]] = None
ptarasiewiczNV's avatar
ptarasiewiczNV committed
448
449
450
     ) -> SchedulerRunningOutputs:
         """Schedule sequence groups that are running.
 
451
@@ -537,6 +548,8 @@ class Scheduler:
ptarasiewiczNV's avatar
ptarasiewiczNV committed
452
453
454
455
456
457
458
459
                 chunked number of tokens are scheduled  if
                 `budget.num_batched_tokens` has not enough capacity to schedule
                 all tokens.
+            finished_remote_prefill_request_ids: Set of request ids of remote
+                prefills that have finished.
     
         Returns:
             SchedulerRunningOutputs.
460
@@ -566,6 +579,24 @@ class Scheduler:
ptarasiewiczNV's avatar
ptarasiewiczNV committed
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
         preempted: List[SequenceGroup] = ret.preempted
         swapped_out: List[SequenceGroup] = ret.swapped_out
 
+        remote_prefilling_queue = self.remote_prefilling
+        leftover_remote_prefilling_sequences: Deque[SequenceGroup] = deque()
+        while remote_prefilling_queue:
+            seq_group = remote_prefilling_queue.popleft()
+            if seq_group.request_id not in finished_prefills:
+                leftover_remote_prefilling_sequences.append(seq_group)
+                continue
+            else:
+                finished_prefills.remove(seq_group.request_id)
+                assert len(seq_group.seqs) == 1
+                seq = seq_group.seqs[0]
+                # we computed all but the last token in prefill, we need to decode the first token on decode
+                seq_group.update_num_computed_tokens(seq.get_len() - 1)
+                seq.status = SequenceStatus.RUNNING
+                seq.data._stage = SequenceStage.DECODE
+                self.running.appendleft(seq_group)
+        remote_prefilling_queue.extendleft(leftover_remote_prefilling_sequences)
+
         running_queue = self.running
         assert len(self._async_stopped) == 0
         while running_queue:
485
@@ -1008,7 +1039,7 @@ class Scheduler:
ptarasiewiczNV's avatar
ptarasiewiczNV committed
486
487
488
489
490
491
492
493
             if curr_loras is not None and lora_int_id > 0:
                 curr_loras.add(lora_int_id)
             waiting_queue.popleft()
-            self._allocate_and_set_running(seq_group)
+            self._allocate_and_set_running_or_remote_prefill(seq_group)
 
             if enable_chunking and self.scheduler_config.is_multi_step:
                 blocks_to_copy: List[Tuple[int, int]] = []
494
@@ -1048,7 +1079,7 @@ class Scheduler:
ptarasiewiczNV's avatar
ptarasiewiczNV committed
495
496
497
498
             num_lookahead_slots=self._get_num_lookahead_slots(
                 is_prefill=True, enable_chunking=enable_chunking))
 
-    def _schedule_default(self) -> SchedulerOutputs:
499
+    def _schedule_default(self, finished_prefills: Optional[Set[str]] = None) -> SchedulerOutputs:
ptarasiewiczNV's avatar
ptarasiewiczNV committed
500
501
502
         """Schedule queued requests.
         
         The current policy is designed to optimize the throughput. First,
503
@@ -1090,7 +1121,8 @@ class Scheduler:
ptarasiewiczNV's avatar
ptarasiewiczNV committed
504
505
506
507
508
         if len(prefills.seq_groups) == 0:
             running_scheduled = self._schedule_running(budget,
                                                        curr_loras,
-                                                       enable_chunking=False)
+                                                       enable_chunking=False,
509
+                                                       finished_prefills=finished_prefills)
ptarasiewiczNV's avatar
ptarasiewiczNV committed
510
511
512
 
             # If any sequence group is preempted, do not swap in any sequence
             # group. because it means there's no slot for new running requests.
513
@@ -1106,7 +1138,12 @@ class Scheduler:
ptarasiewiczNV's avatar
ptarasiewiczNV committed
514
515
516
517
518
519
520
521
522
523
524
525
526
         self.waiting.extendleft(running_scheduled.preempted)
         # Update new running requests.
         if len(prefills.seq_groups) > 0:
-            self.running.extend([s.seq_group for s in prefills.seq_groups])
+            for s in prefills.seq_groups:
+                seq_group = s.seq_group
+                if seq_group.remote_prefill_params is not None and seq_group.remote_prefill_params.is_remote_prefill:
+                    self.remote_prefilling.append(seq_group)
+                else:
+                    self.running.append(seq_group)
 
         self.running.extend(running_scheduled.decode_seq_groups_list)
 
527
@@ -1248,12 +1285,14 @@ class Scheduler:
ptarasiewiczNV's avatar
ptarasiewiczNV committed
528
529
530
531
                        len(running_scheduled.swapped_out)),
         )
 
-    def _schedule(self) -> SchedulerOutputs:
532
+    def _schedule(self, finished_prefills: Optional[Set[str]] = None) -> SchedulerOutputs:
ptarasiewiczNV's avatar
ptarasiewiczNV committed
533
534
         """Schedule queued requests."""
         if self.scheduler_config.chunked_prefill_enabled:
535
+            if finished_prefills:
ptarasiewiczNV's avatar
ptarasiewiczNV committed
536
537
538
539
+                raise ValueError("Chunked prefill does not support remote prefills")
             return self._schedule_chunked_prefill()
         else:
-            return self._schedule_default()
540
+            return self._schedule_default(finished_prefills)
ptarasiewiczNV's avatar
ptarasiewiczNV committed
541
542
543
 
     def _can_append_slots(self, seq_group: SequenceGroup,
                           enable_chunking: bool) -> bool:
544
@@ -1287,14 +1326,15 @@ class Scheduler:
ptarasiewiczNV's avatar
ptarasiewiczNV committed
545
546
547
548
549
         return no_single_seq
 
     def schedule(
-            self
+            self,
550
+            finished_prefills: Optional[Set[str]] = None
ptarasiewiczNV's avatar
ptarasiewiczNV committed
551
552
553
554
555
556
557
558
     ) -> Tuple[List[SequenceGroupMetadata], SchedulerOutputs, bool]:
         # Schedule sequence groups.
         # This function call changes the internal states of the scheduler
         # such as self.running, self.swapped, and self.waiting.
-        scheduler_start_time = time.perf_counter()
 
-        scheduler_outputs: SchedulerOutputs = self._schedule()
+        scheduler_start_time = time.perf_counter()
559
+        scheduler_outputs: SchedulerOutputs = self._schedule(finished_prefills)
ptarasiewiczNV's avatar
ptarasiewiczNV committed
560
561
562
         now = time.time()
 
         if not self.cache_config.enable_prefix_caching:
563
@@ -1333,7 +1373,8 @@ class Scheduler:
ptarasiewiczNV's avatar
ptarasiewiczNV committed
564
565
566
567
568
569
570
571
572
                 encoder_seq_data = None
                 cross_block_table = None
 
-            for seq in seq_group.get_seqs(status=SequenceStatus.RUNNING):
+            running_or_remote_prefilling_seqs = seq_group.get_seqs(status=SequenceStatus.RUNNING) + seq_group.get_seqs(status=SequenceStatus.REMOTE_PREFILLING)
+            for seq in running_or_remote_prefilling_seqs:
                 seq_id = seq.seq_id
                 seq_data[seq_id] = seq.data
                 block_tables[seq_id] = self.block_manager.get_block_table(seq)
573
@@ -1364,6 +1405,10 @@ class Scheduler:
ptarasiewiczNV's avatar
ptarasiewiczNV committed
574
575
576
577
578
579
580
581
582
583
                         < seqs[0].data.get_len()):
                     do_sample = False
 
+            is_remote_prefill = False
+            if is_first_prefill and seq_group.remote_prefill_params is not None and seq_group.remote_prefill_params.is_remote_prefill:
+                is_remote_prefill = True
+
             # It assumes the scheduled_seq_groups is ordered by
             # prefill < decoding.
             if is_first_prefill or not self.scheduler_config.send_delta_data:
584
@@ -1392,6 +1437,7 @@ class Scheduler:
ptarasiewiczNV's avatar
ptarasiewiczNV committed
585
586
587
588
589
590
591
                     if scheduler_outputs.num_prefill_groups > 0 else None,
                     mm_processor_kwargs=seq_group.mm_processor_kwargs,
                     prompt_adapter_request=seq_group.prompt_adapter_request,
+                    do_remote_prefill=is_remote_prefill,
                 )
             else:
                 # When SPMD mode is enabled, we only send delta data except for
592
@@ -1490,10 +1536,13 @@ class Scheduler:
ptarasiewiczNV's avatar
ptarasiewiczNV committed
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
 
             self._async_stopped.clear()
 
-    def _allocate_and_set_running(self, seq_group: SequenceGroup) -> None:
+    def _allocate_and_set_running_or_remote_prefill(self, seq_group: SequenceGroup) -> None:
         self.block_manager.allocate(seq_group)
         for seq in seq_group.get_seqs(status=SequenceStatus.WAITING):
-            seq.status = SequenceStatus.RUNNING
+            if seq_group.remote_prefill_params is not None and seq_group.remote_prefill_params.is_remote_prefill:
+                seq.status = SequenceStatus.REMOTE_PREFILLING
+            else:
+                seq.status = SequenceStatus.RUNNING
 
     def _append_slots(self,
                       seq_group: SequenceGroup,
diff --git a/vllm/distributed/device_communicators/nixl.py b/vllm/distributed/device_communicators/nixl.py
new file mode 100644
610
index 00000000..bc962726
ptarasiewiczNV's avatar
ptarasiewiczNV committed
611
612
--- /dev/null
+++ b/vllm/distributed/device_communicators/nixl.py
613
@@ -0,0 +1,249 @@
ptarasiewiczNV's avatar
ptarasiewiczNV committed
614
615
616
617
618
619
620
+import torch
+from typing import List, Tuple
+from vllm.config import VllmConfig
+from vllm.logger import init_logger
+import msgspec
+import time
+import uuid
621
+from nixl_wrapper import nixl_wrapper as NixlWrapper
ptarasiewiczNV's avatar
ptarasiewiczNV committed
622
623
624
+
+logger = init_logger(__name__)
+
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
+
+def nixl_wrapper_init_patch(self, agent_name, nixl_config):
+    logger.info("Initializing patched NixlWrapper")
+    import nixl_bindings as nixl
+    # Read available backends and device info from nixl_config
+    # For now setting the multithreading to enabled.
+    devices = nixl.nixlAgentConfig(False)
+    init = nixl.nixlUcxInitParams()
+
+    self.name = agent_name
+    self.notifs = {}
+    self.backends = {}
+    self.agent = nixl.nixlAgent(agent_name, devices)
+    self.backends["UCX"] = self.agent.createBackend(init)
+
+    self.nixl_mems = {"DRAM":       nixl.DRAM_SEG,
+                        "VRAM":       nixl.VRAM_SEG,
+                        "cpu":        nixl.DRAM_SEG,
+                        "cuda":       nixl.VRAM_SEG}
+    self.nixl_ops = {"WRITE":       nixl.NIXL_WR_FLUSH,
+                        "READ":        nixl.NIXL_RD_FLUSH,
+                        "WRITE_NOTIF": nixl.NIXL_WR_NOTIF,
+                        "READ_NOTIF":  nixl.NIXL_RD_NOTIF}
+
+    print("Initializied NIXL agent:", agent_name)
+
+NixlWrapper.__init__ = nixl_wrapper_init_patch
+
+
ptarasiewiczNV's avatar
ptarasiewiczNV committed
654
655
656
657
658
659
660
661
662
663
664
+
+class NixlMetadata(
+        msgspec.Struct,
+        omit_defaults=True,  # type: ignore[call-arg]
+        # required for @cached_property.
+        dict=True):
+    engine_id: str
+    agent_metadata: List[bytes]
+    kv_caches_base_addr: List[List[Tuple[int, int]]] # base address for each rank for each layer for keys and values
+
+
665
+class DynemoNixlConnector:
ptarasiewiczNV's avatar
ptarasiewiczNV committed
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
+    def __init__(self, vllm_config: VllmConfig, engine_id: str, rank: int):
+        self.vllm_config = vllm_config
+        self.nixl_wrapper = NixlWrapper(str(uuid.uuid4()), None)
+
+        self.num_layers = None
+        self.num_blocks = None
+        self.block_len = None
+        self.kv_caches_base_addr = {}
+        self.kv_cache_shape = {}
+
+        self._registered_descs = []
+        self._remote_agents = {}
+        self.engine_id = engine_id
+        self.rank = rank
+        self.notifs = {}
+
+    @property
+    def agent_name(self):
+        return self.nixl_wrapper.name
+
+    def register_kv_caches(self, kv_caches: List[torch.Tensor]):
687
688
689
+        caches_data = []
+        self.num_layers = len(kv_caches)
+        _, _, block_size, num_heads, head_dim = kv_caches[0].shape
ptarasiewiczNV's avatar
ptarasiewiczNV committed
690
691
+        self.block_len = block_size * num_heads * head_dim * kv_caches[0].element_size()
+        logger.debug("Per layer kv cache size: %s", kv_caches[0].shape)
692
+
ptarasiewiczNV's avatar
ptarasiewiczNV committed
693
694
695
696
+        kv_caches_base_addr = []
+        for key_cache, value_cache in kv_caches:
+            for cache in [key_cache, value_cache]:
+                base_addr = cache.data_ptr()
697
698
699
700
+                region_len = cache.numel() * cache.element_size()
+                gpu_id = cache.get_device()
+                assert gpu_id > -1, "Tensor is not on GPU"
+                caches_data.append((base_addr, region_len, gpu_id))
ptarasiewiczNV's avatar
ptarasiewiczNV committed
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
+            kv_caches_base_addr.append((key_cache.data_ptr(), value_cache.data_ptr()))
+        self.kv_caches_base_addr[self.engine_id] = kv_caches_base_addr
+
+        descs = self.nixl_wrapper.get_descs(("VRAM", caches_data))
+        self.nixl_wrapper.register_memory(descs)
+        self._registered_descs.append(descs)
+
+    def get_agent_metadata(self):
+        return self.nixl_wrapper.get_agent_metadata()
+    
+    def shutdown(self):
+        for descs_list in self._registered_descs:
+            self.nixl_wrapper.deregister_memory(descs_list)
+        for agent_name in self._remote_agents.values():
+            self.nixl_wrapper.remove_remote_agent(agent_name)
+
717
718
719
720
+    def add_remote_agent(self, engine_id, agent_metadata):
+        agent_name = self.nixl_wrapper.add_remote_agent(agent_metadata)
+        self._remote_agents[engine_id] = agent_name
+        return agent_name
ptarasiewiczNV's avatar
ptarasiewiczNV committed
721
722
723
724
725
726
727
728
729
730
731
732
733
734
+    
+    def get_descs_ids(self, layer_ids, block_ids):
+        if layer_ids == "all":
+            layer_ids = list(range(self.num_layers))
+        if block_ids == "all":
+            block_ids = list(range(self.num_blocks))
+        descs_ids = []
+        for layer_id in layer_ids:
+            for block_id in block_ids:
+                assert block_id < self.num_blocks, f"Block id {block_id} is greater than the number of blocks {self.num_blocks}"
+                descs_ids.append(2 * (self.num_blocks * layer_id + block_id))
+                descs_ids.append(2 * (self.num_blocks * layer_id + block_id) + 1)
+        return descs_ids
+
735
+    def _get_range_descs(self, engine_id, ranges, layer_ids):
ptarasiewiczNV's avatar
ptarasiewiczNV committed
736
737
738
739
740
+        if layer_ids == "all":
+            layer_ids = list(range(self.num_layers))
+        blocks_data = []
+        for layer_id in layer_ids:
+            for range_start, range_end in ranges:
741
742
743
744
745
+                key_base_addr, value_base_addr = self.kv_caches_base_addr[engine_id][layer_id]
+                start_offset = range_start * self.block_len
+                blocks_len = (range_end - range_start + 1) * self.block_len
+                blocks_data.append((key_base_addr + start_offset, blocks_len, self.rank))
+                blocks_data.append((value_base_addr + start_offset, blocks_len, self.rank))
ptarasiewiczNV's avatar
ptarasiewiczNV committed
746
747
748
749
750
751
752
753
754
755
756
757
+        return self.nixl_wrapper.get_descs(("VRAM", blocks_data))
+    
+    def _get_ranges(self, block_ids):
+        # This function should return a list of ranges of block ids that are contiguous
+        # For example, if block_ids is [0, 1, 2, 4, 5, 6], the function should return [[0, 2], [4, 6]]
+        # The ranges are sorted by the starting block id
+        # The function should also make sure that the block ids are contiguous
+        # If the block ids are not contiguous, the function should raise an error
+        sorted_block_ids = sorted(block_ids)
+        ranges = []
+        for i in range(len(sorted_block_ids)):
+            if i == 0 or sorted_block_ids[i] != sorted_block_ids[i-1] + 1:
758
+                ranges.append([sorted_block_ids[i]])
ptarasiewiczNV's avatar
ptarasiewiczNV committed
759
+            else:
760
+                ranges[-1].append(sorted_block_ids[i])
ptarasiewiczNV's avatar
ptarasiewiczNV committed
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
+        return ranges
+
+    def _get_same_length_ranges(self, src_ranges, dst_ranges):
+        # This function should return a list of ranges for both src and dst so that corresponding ranges are the same length
+        # For example, if src_ranges is [[0, 2] [4, 8]] and dst_ranges is [[1, 3], [5, 7], [9, 10]]
+        # The function should return ([[0, 2], [4, 6], [7, 8]], [[1, 3], [5, 7], [9, 10]])
+        src_overlapping_ranges, dst_overlapping_ranges = [], []
+        
+        src_idx, dst_idx = 0, 0
+        while src_idx < len(src_ranges) and dst_idx < len(dst_ranges):
+            src_range = src_ranges[src_idx]
+            dst_range = dst_ranges[dst_idx]
+            
+            # Calculate the length of each range
+            src_len = src_range[-1] - src_range[0] + 1
+            dst_len = dst_range[-1] - dst_range[0] + 1
+            
+            # If ranges have the same length, add them directly
+            if src_len == dst_len:
+                src_overlapping_ranges.append([src_range[0], src_range[-1]])
+                dst_overlapping_ranges.append([dst_range[0], dst_range[-1]])
+                src_idx += 1
+                dst_idx += 1
+            # If source range is longer, split it
+            elif src_len > dst_len:
+                src_overlapping_ranges.append([src_range[0], src_range[0] + dst_len - 1])
+                dst_overlapping_ranges.append([dst_range[0], dst_range[-1]])
+                # Update source range for next iteration
+                src_ranges[src_idx] = [src_range[0] + dst_len, src_range[-1]]
+                dst_idx += 1
+            # If destination range is longer, split it
+            else:  # src_len < dst_len
+                src_overlapping_ranges.append([src_range[0], src_range[-1]])
+                dst_overlapping_ranges.append([dst_range[0], dst_range[0] + src_len - 1])
+                # Update destination range for next iteration
+                dst_ranges[dst_idx] = [dst_range[0] + src_len, dst_range[-1]]
+                src_idx += 1
+        
+        return src_overlapping_ranges, dst_overlapping_ranges
+                
+
+    
803
804
+    def transfer_mem(self, src_block_ids, dst_block_ids, dst_engine_id, notify_msg):
+
ptarasiewiczNV's avatar
ptarasiewiczNV committed
805
806
807
808
809
810
811
812
813
814
815
+        start_time = time.perf_counter()
+        logger.debug("Transferring memory from %s to %s with notify message %s", self.agent_name, dst_engine_id, notify_msg)
+
+        # hongkuanz: we send isl[:-1] tokens to the prefill where the kv for the last
+        # isl[-1] token is calculated in the first iteration in decode.
+        # If isl equals to a multiple of tokens_per_block + 1, prefill engine will have \
+        # one less block due to the missing last token.
+        dst_block_ids = dst_block_ids[:len(src_block_ids)]
+
+        src_ranges = self._get_ranges(src_block_ids)
+        dst_ranges = self._get_ranges(dst_block_ids)
816
+        src_overlapping_ranges, dst_overlapping_ranges = self._get_same_length_ranges(src_ranges, dst_ranges)
ptarasiewiczNV's avatar
ptarasiewiczNV committed
817
+
818
+        logger.debug("Got %s overlapping ranges for %s blocks", len(src_overlapping_ranges), len(src_block_ids))
ptarasiewiczNV's avatar
ptarasiewiczNV committed
819
+
820
+        logger.debug("Time to get ranges: %s ms", time.perf_counter() - start_time)
ptarasiewiczNV's avatar
ptarasiewiczNV committed
821
+
822
823
+        src_descs = self._get_range_descs(self.engine_id, src_overlapping_ranges, "all")
+        dst_descs = self._get_range_descs(dst_engine_id, dst_overlapping_ranges, "all")
ptarasiewiczNV's avatar
ptarasiewiczNV committed
824
+
825
+        logger.debug("Time to get descs: %s ms", (time.perf_counter() - start_time) * 1000)
ptarasiewiczNV's avatar
ptarasiewiczNV committed
826
+
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
+        handle = self.nixl_wrapper.initialize_xfer(src_descs, dst_descs, self._remote_agents[dst_engine_id], notify_msg, "WRITE")
+        logger.debug("Time to initialize xfer: %s ms", (time.perf_counter() - start_time) * 1000)
+        logger.debug("Transfer handle: %s", handle)
+        status = self.nixl_wrapper.transfer(handle)
+        logger.debug("Time to transfer: %s ms", (time.perf_counter() - start_time) * 1000)
+        logger.debug("Transfer status: %s", status)
+        # TODO ptarasiewicz: remove blocking transfer mem
+        # add scheduler check for transfer done
+        while True:
+            xfer_state = self.nixl_wrapper.check_xfer_state(handle)
+            if xfer_state == "ERR":
+                raise RuntimeError("Transfer failed")
+            elif xfer_state == "DONE":
+                logger.debug("Transfer done")
+                break
+            elif xfer_state == "PROC":
+                time.sleep(0.01)
+            else:
+                raise RuntimeError("Unknown transfer state")
+        logger.debug("Time to wait for transfer: %s ms", (time.perf_counter() - start_time) * 1000)
+        self.nixl_wrapper.abort_xfer(handle)
+        logger.debug("Time to abort xfer: %s ms", (time.perf_counter() - start_time) * 1000)
+        logger.debug("Transfer time: %s ms", (time.perf_counter() - start_time) * 1000)
ptarasiewiczNV's avatar
ptarasiewiczNV committed
850
851
852
853
854
855
856
857
858
859
860
861
862
+
+    def deserialize_descs(self, serialized_descs):
+        return self.nixl_wrapper.deserialize_descs(serialized_descs)
+    
+    def get_notifs(self):
+        self.notifs = self.nixl_wrapper.agent.getNotifs(self.notifs)
+        return self.notifs
+    
+    def get_new_notifs(self):
+        return self.nixl_wrapper.agent.getNotifs({})
+    
+    def add_remote_kv_caches_base_addr(self, engine_id, kv_caches_base_addr):
+        self.kv_caches_base_addr[engine_id] = kv_caches_base_addr
863
diff --git a/vllm/distributed/kv_transfer/kv_connector/factory.py b/vllm/distributed/kv_transfer/kv_connector/factory.py
864
index fe480533..61a357d0 100644
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
--- a/vllm/distributed/kv_transfer/kv_connector/factory.py
+++ b/vllm/distributed/kv_transfer/kv_connector/factory.py
@@ -27,13 +27,13 @@ class KVConnectorFactory:
 
     @classmethod
     def create_connector(cls, rank: int, local_rank: int,
-                         config: "VllmConfig") -> KVConnectorBase:
+                         config: "VllmConfig", world_group) -> KVConnectorBase:
         connector_name = config.kv_transfer_config.kv_connector
         if connector_name not in cls._registry:
             raise ValueError(f"Unsupported connector type: {connector_name}")
 
         connector_cls = cls._registry[connector_name]()
-        return connector_cls(rank, local_rank, config)
+        return connector_cls(rank, local_rank, config, world_group)
 
 
 # Register various connectors here.
883
884
885
886
887
888
@@ -48,3 +48,8 @@ KVConnectorFactory.register_connector(
     "MooncakeConnector",
     "vllm.distributed.kv_transfer.kv_connector.simple_connector",
     "SimpleConnector")
+
+KVConnectorFactory.register_connector(
889
890
891
+    "DynemoNcclConnector",
+    "vllm.distributed.kv_transfer.kv_connector.dynemo_connector",
+    "DynemoConnector")
892
\ No newline at end of file
893
diff --git a/vllm/distributed/kv_transfer/kv_connector/simple_connector.py b/vllm/distributed/kv_transfer/kv_connector/simple_connector.py
894
index 2033e976..e33919c1 100644
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
--- a/vllm/distributed/kv_transfer/kv_connector/simple_connector.py
+++ b/vllm/distributed/kv_transfer/kv_connector/simple_connector.py
@@ -8,13 +8,15 @@ MooncakePipe.
 
 But the logic can be extended to support other pipe and lookup buffer.
 """
+import re
 from typing import TYPE_CHECKING, List, Optional, Tuple, Union
 
 import torch
 
 from vllm import _custom_ops as ops
-from vllm.config import VllmConfig
+from vllm.config import VllmConfig, KVTransferConfig
 from vllm.distributed.kv_transfer.kv_connector.base import KVConnectorBase
+from vllm.distributed.utils import StatelessProcessGroup
 from vllm.distributed.kv_transfer.kv_lookup_buffer.simple_buffer import (
     SimpleBuffer)
 from vllm.logger import init_logger
914
@@ -33,6 +35,7 @@ class SimpleConnector(KVConnectorBase):
915
916
917
918
919
920
921
         rank: int,
         local_rank: int,
         config: VllmConfig,
+        world_group,
     ):
 
         self.config = config.kv_transfer_config
922
@@ -71,20 +74,31 @@ class SimpleConnector(KVConnectorBase):
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
         self.producer_signal_pipe: Union[PyNcclPipe, MooncakePipe]
         self.consumer_signal_pipe: Union[PyNcclPipe, MooncakePipe]
 
+        self._broadcast_and_enhance_kv_config(rank, config, world_group)
+
+        self.kv_group_rank = self._get_kv_group_rank(self.config.kv_rank, rank, self.config)
+        self.tp_size = config.parallel_config.tensor_parallel_size
+
         # 2 pipes for every rank in the world
-        port_offset_base = 2 * rank
+        if self.config.is_kv_producer:
+            port_offset_base = 2 * rank + 1
+        else:
+            port_offset_base = 2 * (rank // self.config.tensor_parallel_multiplier) + 1
 
+        self.local_kv_rank = rank % self.config.tensor_parallel_multiplier
         # In disaggregated prefill, the prefill vLLM only uses send pipe
         # and the decode vLLM only uses recv pipe
         if self.config.is_kv_producer:
 
             if self.config.kv_connector == "PyNcclConnector":
                 self.producer_data_pipe = PyNcclPipe(
+                    kv_group_rank=self.kv_group_rank,
                     local_rank=local_rank,
                     config=self.config,
                     port_offset=port_offset_base,
                 )
                 self.producer_signal_pipe = PyNcclPipe(
+                    kv_group_rank=self.kv_group_rank,
                     local_rank=local_rank,
                     config=self.config,
                     port_offset=port_offset_base + 1,
955
@@ -108,11 +122,13 @@ class SimpleConnector(KVConnectorBase):
956
957
958
959
960
961
962
963
964
965
966
967
968
             # its recv pipe to the send pipe of KV producder
             if self.config.kv_connector == "PyNcclConnector":
                 self.consumer_data_pipe = PyNcclPipe(
+                    kv_group_rank=self.kv_group_rank,
                     local_rank=local_rank,
                     config=self.config,
                     port_offset=port_offset_base,
                 )
                 self.consumer_signal_pipe = PyNcclPipe(
+                    kv_group_rank=self.kv_group_rank,
                     local_rank=local_rank,
                     config=self.config,
                     port_offset=port_offset_base + 1,
969
@@ -131,21 +147,25 @@ class SimpleConnector(KVConnectorBase):
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
                 self.config.kv_buffer_size,
             )
 
-    def select(self, input_tokens: Optional[torch.Tensor],
+    def select(self, source_rank: int, input_tokens: Optional[torch.Tensor],
                roi: Optional[torch.Tensor]) -> List[Optional[torch.Tensor]]:
 
+        logger.info("Selecting KV caches and hidden states for source rank %d", source_rank)
+
         assert self.consumer_buffer is not None, "Please initialize the "\
             "consumer buffer before calling select."
-        return self.consumer_buffer.drop_select(input_tokens, roi)
+        return self.consumer_buffer.drop_select(source_rank, self.local_kv_rank, input_tokens, roi)
 
-    def insert(self, input_tokens: torch.Tensor, roi: torch.Tensor,
+    def insert(self, kv_group_rank: int, target_rank: int, input_tokens: torch.Tensor, roi: torch.Tensor,
                key: torch.Tensor, value: torch.Tensor,
                hidden: torch.Tensor) -> None:
 
+        logger.info("Inserting KV caches and hidden states for kv_group_rank %d, target rank %d", kv_group_rank, target_rank)
+
         assert self.producer_buffer is not None, "Please initialize the "\
             "producer buffer before calling insert."
 
-        self.producer_buffer.insert(input_tokens, roi, key, value, hidden)
+        self.producer_buffer.insert(kv_group_rank, target_rank, input_tokens, roi, key, value, hidden)
 
     def send_kv_caches_and_hidden_states(
         self,
999
@@ -161,12 +181,20 @@ class SimpleConnector(KVConnectorBase):
1000
1001
1002
1003
1004
1005
         slot_mapping_flat = model_input.attn_metadata.slot_mapping.flatten()
         start_layer = model_executable.model.start_layer
         end_layer = model_executable.model.end_layer
+        request_ids = list(model_input.request_ids_to_seq_ids.keys())
 
         model_config = model_executable.model.config
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
-        num_heads = int(model_config.num_key_value_heads / self.tp_size)
-        hidden_size = model_config.hidden_size
-        num_attention_heads = model_config.num_attention_heads
-        head_size = int(hidden_size / num_attention_heads)
+        is_deepseek = "deepseek" in model_config.architectures[0].lower()
+        if not is_deepseek:
+            num_heads = int(model_config.num_key_value_heads / self.tp_size)
+            hidden_size = model_config.hidden_size
+            num_attention_heads = model_config.num_attention_heads
+            head_size = int(hidden_size / num_attention_heads)
+        else:
+            num_heads = int(model_config.num_key_value_heads / self.tp_size)
+            hidden_size = model_config.hidden_size
+            num_attention_heads = model_config.num_attention_heads
+            head_size = int(4.5 * hidden_size / num_attention_heads)
 
         # query_lens contains new KV caches that are added to vLLM.
         # so we will send them to decode instance
@@ -175,27 +203,40 @@ class SimpleConnector(KVConnectorBase):
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
             start_pos = sum(seq_lens[:idx])
             end_pos = start_pos + slen
             current_tokens = input_tokens_tensor[start_pos:end_pos]
+            current_request_id = request_ids[idx]
+            _, decode_kv_rank = self.parse_request_id(current_request_id)
+            starting_kv_group_rank = self._get_kv_group_rank(decode_kv_rank, 0, self.config)
+
+            for target_rank in range(self.config.tensor_parallel_multiplier):
 
-            keys, values = [], []
1035
+                keys, values = [], []
1036
1037
1038
 
-            for layer_id in range(start_layer, end_layer):
-                kv_cache = kv_caches[layer_id - start_layer]
1039
1040
+                for layer_id in range(start_layer, end_layer):
+                    kv_cache = kv_caches[layer_id - start_layer]
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
 
-                key_cache = kv_cache[0].reshape(-1, num_heads, head_size)
-                value_cache = kv_cache[1].reshape(-1, num_heads, head_size)
+                    current_slot_mapping = slot_mapping_flat[start_pos:end_pos]
 
-                current_slot_mapping = slot_mapping_flat[start_pos:end_pos]
+                    num_heads_per_rank = num_heads // self.config.tensor_parallel_multiplier
+                    head_start = target_rank * num_heads_per_rank
+                    head_end = head_start + num_heads_per_rank
 
-                keys.append(key_cache[current_slot_mapping].unsqueeze(0))
-                values.append(value_cache[current_slot_mapping].unsqueeze(0))
1053
1054
1055
1056
1057
1058
1059
1060
1061
+                    if not is_deepseek:
+                        key_cache = kv_cache[0].reshape(-1, num_heads, head_size)
+                        value_cache = kv_cache[1].reshape(-1, num_heads, head_size)
+                        keys.append(key_cache[current_slot_mapping, head_start:head_end].unsqueeze(0))
+                        values.append(value_cache[current_slot_mapping, head_start:head_end].unsqueeze(0))
+                    else:
+                        key_cache = kv_cache
+                        keys.append(key_cache[current_slot_mapping].unsqueeze(0))
+                        values.append(torch.empty(0))
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
 
-            keys = torch.cat(keys, dim=0)
-            values = torch.cat(values, dim=0)
+                keys = torch.cat(keys, dim=0)
+                values = torch.cat(values, dim=0)
 
-            self.insert(current_tokens,
-                        torch.ones_like(current_tokens,
-                                        dtype=bool), keys, values,
-                        hidden_or_intermediate_states[start_pos:end_pos])
+                self.insert(starting_kv_group_rank, target_rank, current_tokens,
+                            torch.ones_like(current_tokens,
+                                            dtype=bool), keys, values,
+                            hidden_or_intermediate_states[start_pos:end_pos])
 
         logger.debug("[rank%d]: KV send DONE.", torch.distributed.get_rank())
 
1079
@@ -215,6 +256,7 @@ class SimpleConnector(KVConnectorBase):
1080
1081
1082
1083
1084
1085
1086
         input_tokens_tensor = model_input.input_tokens
         seq_lens = model_input.attn_metadata.seq_lens
         slot_mapping = model_input.attn_metadata.slot_mapping.flatten()
+        request_ids = list(model_input.request_ids_to_seq_ids.keys())
 
         hidden_or_intermediate_states_for_one_req = []
 
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
@@ -222,6 +264,9 @@ class SimpleConnector(KVConnectorBase):
         num_computed_tokens_list = []
         start_pos_list = []
 
+        model_config = model_executable.model.config
+        is_deepseek = "deepseek" in model_config.architectures[0].lower()
+
         # enumerate different requests
         # FIXME(Kuntai): This impl assumes that all requests are prefill.
         for idx, slen in enumerate(seq_lens):
@@ -229,13 +274,15 @@ class SimpleConnector(KVConnectorBase):
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
             start_pos = sum(seq_lens[:idx])
             end_pos = start_pos + slen
             current_tokens = input_tokens_tensor[start_pos:end_pos]
+            current_request_id = request_ids[idx]
+            prefill_rank, _ = self.parse_request_id(current_request_id)
             num_tokens = slen
 
             # collecting data for rebuilding the input
             input_tokens_list.append(current_tokens)
             start_pos_list.append(start_pos)
 
-            ret = self.select(current_tokens,
+            ret = self.select(prefill_rank, current_tokens,
                               torch.ones_like(current_tokens, dtype=bool))
             if ret[0] is None:
                 # didn't find any match.
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
@@ -267,19 +314,25 @@ class SimpleConnector(KVConnectorBase):
                 kv_cache = kv_caches[i - model_executable.model.start_layer]
                 layer = model_executable.model.layers[i]
 
-                key_cache, value_cache = kv_cache[0], kv_cache[1]
-                ops.reshape_and_cache_flash(
-                    keys[i - model_executable.model.start_layer].to(
-                        key_cache.device),
-                    values[i - model_executable.model.start_layer].to(
-                        value_cache.device),
-                    key_cache,
-                    value_cache,
-                    slot_mapping[start_pos:end_pos],
-                    layer.self_attn.attn.kv_cache_dtype,
-                    layer.self_attn.attn._k_scale,
-                    layer.self_attn.attn._v_scale,
-                )
+                if not is_deepseek:
+                    key_cache, value_cache = kv_cache[0], kv_cache[1]
+                    ops.reshape_and_cache_flash(
+                        keys[i - model_executable.model.start_layer].to(
+                            key_cache.device),
+                        values[i - model_executable.model.start_layer].to(
+                            value_cache.device),
+                        key_cache,
+                        value_cache,
+                        slot_mapping[start_pos:end_pos],
+                        layer.self_attn.attn.kv_cache_dtype,
+                        layer.self_attn.attn._k_scale,
+                        layer.self_attn.attn._v_scale,
+                    )
+                else:
+                    key_cache = kv_cache
+                    copy_from =keys[i - model_executable.model.start_layer].to(
+                            key_cache.device)
+                    kv_cache[slot_mapping[start_pos:end_pos]] = copy_from
 
             hidden_or_intermediate_states_for_one_req.append(hidden)
 
@@ -312,3 +365,77 @@ class SimpleConnector(KVConnectorBase):
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
             # MooncakePipe reuses data_pipe for signal_pipe, so we only have to
             # close the data_pipe.
             pass
+
+    @staticmethod
+    def parse_request_id(request_id):
+        # Regular expression to match the ranks
+        pattern = r"___prefill_kv_rank_(\d+)___decode_kv_rank_(\d+)"
+        
+        # Use re.search to find the pattern in the request_id
+        match = re.search(pattern, request_id)
+        
+        if match:
+            # Extract the ranks
+            prefill_rank = int(match.group(1))
+            decode_rank = int(match.group(2))
+            
+            return prefill_rank, decode_rank
+        else:
+            return None, None
+
+    
+
+    def _get_kv_group_rank(self, kv_rank: int, rank: int, config: KVTransferConfig) -> int:
+        if kv_rank < config.kv_producers_parallel_size:
+            return kv_rank
+        
+        kv_consumer_rank = kv_rank - config.kv_producers_parallel_size
+        return config.kv_producers_parallel_size + kv_consumer_rank * config.tensor_parallel_multiplier + rank % config.tensor_parallel_multiplier
+
+    def _broadcast_and_enhance_kv_config(self, rank: int, config: VllmConfig, world_group):
+        if rank == 0:
+            if self.config.kv_connector == "PyNcclConnector":
+                config_group = StatelessProcessGroup.create(
+                    host=self.config.kv_ip,
+                    port=self.config.kv_port,
+                    rank=self.config.kv_rank,
+                    world_size=self.config.kv_parallel_size,
+                )
+                parallel_configs = config_group.all_gather_obj({
+                    "kv_role": self.config.kv_role,
+                    "tensor_parallel_size": config.parallel_config.tensor_parallel_size,
+                    "pipeline_parallel_size": config.parallel_config.pipeline_parallel_size,
+                })
+                logger.debug("parallel_configs: %s", parallel_configs)
+                kv_config_enhanced = {
+                    "kv_producers_tensor_parallel_size": None,
+                    "kv_consumers_tensor_parallel_size": None,
+                    "kv_producers_pipeline_parallel_size": None,
+                    "kv_consumers_pipeline_parallel_size": None,
+                    "kv_producers_parallel_size": 0,
+                }
+                for parallel_config in parallel_configs:
+                    kv_role = parallel_config["kv_role"]
+                    assert parallel_config["pipeline_parallel_size"] == 1, f"Only pipeline parallel size 1 is supported for kv transfer instances"
+                    
+                    if kv_role == "kv_producer":
+                        kv_config_enhanced["kv_producers_parallel_size"] += 1
+                    if kv_config_enhanced[f"{kv_role}s_tensor_parallel_size"] is None:
+                        kv_config_enhanced[f"{kv_role}s_tensor_parallel_size"] = parallel_config["tensor_parallel_size"]
+                        kv_config_enhanced[f"{kv_role}s_pipeline_parallel_size"] = parallel_config["pipeline_parallel_size"]
+                    else:
+                        assert kv_config_enhanced[f"{kv_role}s_tensor_parallel_size"] == parallel_config["tensor_parallel_size"], f"All kv {kv_role}s should have the same tensor parallel size"
+                        assert kv_config_enhanced[f"{kv_role}s_pipeline_parallel_size"] == parallel_config["pipeline_parallel_size"], f"All kv {kv_role}s should have the same pipeline parallel size"
+                world_group.broadcast_object(kv_config_enhanced)
+
+            else:
1221
+                raise NotImplementedError("MooncakeConnector is not supported in Dynemo Distributed vllm patch")
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
+        else:
+            kv_config_enhanced = world_group.broadcast_object()
+        logger.info("kv_config_enhanced: %s", kv_config_enhanced)
+
+        self.config.kv_producers_tensor_parallel_size = kv_config_enhanced["kv_producers_tensor_parallel_size"]
+        self.config.kv_consumers_tensor_parallel_size = kv_config_enhanced["kv_consumers_tensor_parallel_size"]
+        self.config.kv_producers_pipeline_parallel_size = kv_config_enhanced["kv_producers_pipeline_parallel_size"]
+        self.config.kv_consumers_pipeline_parallel_size = kv_config_enhanced["kv_consumers_pipeline_parallel_size"]
+        self.config.kv_producers_parallel_size = kv_config_enhanced["kv_producers_parallel_size"]
\ No newline at end of file
1232
diff --git a/vllm/distributed/kv_transfer/kv_connector/dynemo_connector.py b/vllm/distributed/kv_transfer/kv_connector/dynemo_connector.py
1233
1234
1235
new file mode 100644
index 00000000..cb3b3660
--- /dev/null
1236
+++ b/vllm/distributed/kv_transfer/kv_connector/dynemo_connector.py
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
@@ -0,0 +1,350 @@
+# SPDX-License-Identifier: Apache-2.0
+"""
+Simple KV Cache Connector for Distributed Machine Learning Inference
+
+The SimpleConnector transfers KV caches between prefill vLLM worker (KV cache 
+producer) and decode vLLM worker (KV cache consumer) using PyNcclPipe or
+MooncakePipe.
+
+But the logic can be extended to support other pipe and lookup buffer.
+"""
+import re
+from typing import TYPE_CHECKING, List, Optional, Tuple, Union
+
+import torch
+
+from vllm import _custom_ops as ops
+from vllm.config import VllmConfig, KVTransferConfig
+from vllm.distributed.kv_transfer.kv_connector.base import KVConnectorBase
+from vllm.distributed.utils import StatelessProcessGroup
+from vllm.distributed.kv_transfer.kv_lookup_buffer.simple_buffer import (
+    SimpleBuffer)
+from vllm.logger import init_logger
+from vllm.sequence import IntermediateTensors
+
+if TYPE_CHECKING:
+    from vllm.worker.model_runner import ModelInputForGPUWithSamplingMetadata
+
+logger = init_logger(__name__)
+
+
1268
+class DynemoConnector(KVConnectorBase):
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
+
+    def __init__(
+        self,
+        rank: int,
+        local_rank: int,
+        config: VllmConfig,
+        world_group,
+    ):
+
+        self.config = config.kv_transfer_config
+        self.tp_size = config.parallel_config.tensor_parallel_size
+        self.rank = rank
+
1282
1283
+        if self.config.kv_connector != "DynemoNcclConnector":
+            raise NotImplementedError("Only DynemoNcclConnector is supported by the DynemoConnector class")
1284
1285
1286
+
+        from vllm.distributed.kv_transfer.kv_pipe.pynccl_pipe import (
+            PyNcclPipe)
1287
1288
+        from vllm.distributed.kv_transfer.kv_pipe.dynemo_nccl_pipe import (
+            DynemoNcclDataPlane)
1289
1290
+        
+        logger.info(
1291
+            "Initializing DynemoNcclConnector under kv_transfer_config %s",
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
+            self.config)
+
+        self.lookup_buffer_size = self.config.kv_buffer_size
+
+        self.producer_data_pipe: PyNcclPipe
+        self.consumer_data_pipe: PyNcclPipe
+        self.producer_signal_pipe: PyNcclPipe
+        self.consumer_signal_pipe: PyNcclPipe
+
+        self._broadcast_and_enhance_kv_config(rank, config, world_group)
+
+        self.kv_group_rank = self._get_kv_group_rank(self.config.kv_rank, rank, self.config)
+        self.tp_size = config.parallel_config.tensor_parallel_size
+
+        # 2 pipes for every rank in the world
+        if self.config.is_kv_producer:
+            port_offset_base = rank + 1
+        else:
+            port_offset_base = rank // self.config.tensor_parallel_multiplier + 1
+
+
+        self.local_kv_rank = rank % self.config.tensor_parallel_multiplier
+        self.global_kv_rank = self._get_global_kv_rank(self.config.kv_rank, rank, self.config)
+
+        self.data_pipe = PyNcclPipe(
+            kv_group_rank=self.kv_group_rank,
+            local_rank=local_rank,
+            config=self.config,
+            port_offset=port_offset_base,
+        )
+
1323
+        self.data_plane = DynemoNcclDataPlane(
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
+            data_pipe=self.data_pipe,
+            port=self._get_data_plane_port(self.global_kv_rank),
+        )
+
+    def send_kv_caches_and_hidden_states(
+        self,
+        model_executable: torch.nn.Module,
+        model_input: "ModelInputForGPUWithSamplingMetadata",
+        kv_caches: List[torch.Tensor],
+        hidden_or_intermediate_states: Union[torch.Tensor,
+                                             IntermediateTensors],
+    ) -> None:
+
+        input_tokens_tensor = model_input.input_tokens
+        seq_lens = model_input.attn_metadata.seq_lens
+        slot_mapping_flat = model_input.attn_metadata.slot_mapping.flatten()
+        start_layer = model_executable.model.start_layer
+        end_layer = model_executable.model.end_layer
+        request_ids = list(model_input.request_ids_to_seq_ids.keys())
+
+        model_config = model_executable.model.config
+        is_deepseek = "deepseek" in model_config.architectures[0].lower()
+        if not is_deepseek:
+            num_heads = int(model_config.num_key_value_heads / self.tp_size)
+            hidden_size = model_config.hidden_size
+            num_attention_heads = model_config.num_attention_heads
+            head_size = int(hidden_size / num_attention_heads)
+        else:
+            num_heads = int(model_config.num_key_value_heads / self.tp_size)
+            hidden_size = model_config.hidden_size
+            num_attention_heads = model_config.num_attention_heads
+            head_size = int(4.5 * hidden_size / num_attention_heads)
+
+        # query_lens contains new KV caches that are added to vLLM.
+        # so we will send them to decode instance
+        # FIXME(Kuntai): This assume that all requests are prefill.
+        for idx, slen in enumerate(seq_lens):
+            start_pos = sum(seq_lens[:idx])
+            end_pos = start_pos + slen
+            current_tokens = input_tokens_tensor[start_pos:end_pos]
+            current_request_id = request_ids[idx]
+            decode_hostname, decode_kv_rank = self.parse_request_id(current_request_id)
+            decode_first_global_rank = self._get_global_kv_rank(decode_kv_rank, self.rank * self.config.tensor_parallel_multiplier, self.config)
+
+            for target_rank in range(self.config.tensor_parallel_multiplier):
+
+                keys, values = [], []
+
+                for layer_id in range(start_layer, end_layer):
+                    kv_cache = kv_caches[layer_id - start_layer]
+
+                    current_slot_mapping = slot_mapping_flat[start_pos:end_pos]
+
+                    num_heads_per_rank = num_heads // self.config.tensor_parallel_multiplier
+                    head_start = target_rank * num_heads_per_rank
+                    head_end = head_start + num_heads_per_rank
+
+                    if not is_deepseek:
+                        key_cache = kv_cache[0].reshape(-1, num_heads, head_size)
+                        value_cache = kv_cache[1].reshape(-1, num_heads, head_size)
+                        keys.append(key_cache[current_slot_mapping, head_start:head_end].unsqueeze(0))
+                        values.append(value_cache[current_slot_mapping, head_start:head_end].unsqueeze(0))
+                    else:
+                        key_cache = kv_cache
+                        keys.append(key_cache[current_slot_mapping].unsqueeze(0))
+                        values.append(torch.empty(0))
+
+                keys = torch.cat(keys, dim=0)
+                values = torch.cat(values, dim=0)
+
+                decode_global_rank = decode_first_global_rank + target_rank
+                decode_port = self._get_data_plane_port(decode_global_rank)
+                partial_hidden_or_intermediate_states = hidden_or_intermediate_states[start_pos:end_pos]
+                self._send(decode_hostname, decode_port, current_request_id, keys, values,
+                            partial_hidden_or_intermediate_states)
+
+        logger.debug("[rank%d]: KV send DONE.", torch.distributed.get_rank())
+
+    def recv_kv_caches_and_hidden_states(
+        self, model_executable: torch.nn.Module,
+        model_input: "ModelInputForGPUWithSamplingMetadata",
+        kv_caches: List[torch.Tensor]
+    ) -> Tuple[Union[torch.Tensor, IntermediateTensors], bool,
+               "ModelInputForGPUWithSamplingMetadata"]:
+
+        # When bypass_model_exec is set to False, it means that at least for one
+        # request its corresponding KV cache or hidden state is missing.
+        # In this case we need to do prefilling to recompute missing KV cache
+        # and hidden states.
+        bypass_model_exec = True
+
+        input_tokens_tensor = model_input.input_tokens
+        seq_lens = model_input.attn_metadata.seq_lens
+        slot_mapping = model_input.attn_metadata.slot_mapping.flatten()
+        request_ids = list(model_input.request_ids_to_seq_ids.keys())
+
+        hidden_or_intermediate_states_for_one_req = []
+
+        input_tokens_list = []
+        start_pos_list = []
+
+        model_config = model_executable.model.config
+        is_deepseek = "deepseek" in model_config.architectures[0].lower()
+
+        # enumerate different requests
+        # FIXME(Kuntai): This impl assumes that all requests are prefill.
+        for idx, slen in enumerate(seq_lens):
+
+            start_pos = sum(seq_lens[:idx])
+            end_pos = start_pos + slen
+            current_tokens = input_tokens_tensor[start_pos:end_pos]
+            current_request_id = request_ids[idx]
+            num_tokens = slen
+
+            # collecting data for rebuilding the input
+            input_tokens_list.append(current_tokens)
+            start_pos_list.append(start_pos)
+
+            ret = self._recv(current_request_id)
+            keys: torch.Tensor = ret[0]
+            values: torch.Tensor = ret[1]
+            hidden: torch.Tensor = ret[2]
+
+            # put received KV caches into paged memory
+            for i in range(model_executable.model.start_layer,
+                           model_executable.model.end_layer):
+
+                kv_cache = kv_caches[i - model_executable.model.start_layer]
+                layer = model_executable.model.layers[i]
+
+                if not is_deepseek:
+                    key_cache, value_cache = kv_cache[0], kv_cache[1]
+                    ops.reshape_and_cache_flash(
+                        keys[i - model_executable.model.start_layer].to(
+                            key_cache.device),
+                        values[i - model_executable.model.start_layer].to(
+                            value_cache.device),
+                        key_cache,
+                        value_cache,
+                        slot_mapping[start_pos:end_pos],
+                        layer.self_attn.attn.kv_cache_dtype,
+                        layer.self_attn.attn._k_scale,
+                        layer.self_attn.attn._v_scale,
+                    )
+                else:
+                    key_cache = kv_cache
+                    copy_from =keys[i - model_executable.model.start_layer].to(
+                            key_cache.device)
+                    kv_cache[slot_mapping[start_pos:end_pos]] = copy_from
+
+            hidden_or_intermediate_states_for_one_req.append(hidden)
+
+        if not bypass_model_exec:
+            # Some of the KV cache is not retrieved
+            # Here we will fall back to normal model forwarding
+            # But optionally you can adjust model_input so that you only do
+            # prefilling on those tokens that are missing KV caches.
+            logger.debug(
+                "[rank%d]: Failed to receive all KVs and hidden "
+                "states, redo model forwarding.", torch.distributed.get_rank())
+            hidden_or_intermediate_states = None
+
+        else:
+            logger.debug(
+                "[rank%d]: Successfully received all KVs and hidden "
+                "states, skip model forwarding.", torch.distributed.get_rank())
+            hidden_or_intermediate_states = torch.cat(
+                hidden_or_intermediate_states_for_one_req, dim=0)
+
+        return hidden_or_intermediate_states, bypass_model_exec, model_input
+
+    def close(self):
+        self.data_pipe.close()
+        # self.data_plane.close()
+
+    @staticmethod
+    def parse_request_id(request_id: str) -> Tuple[str, int]:
+        # Regular expression to match the string hostname and integer decode_kv_rank
+        pattern = r"___decode_hostname_(.*)___decode_kv_rank_(\d+)"
+        
+        # Use re.search to find the pattern in the request_id
+        match = re.search(pattern, request_id)
+        if match:
+            # Extract the ranks
+            decode_hostname = match.group(1)
+            decode_rank = int(match.group(2))
+            
+            return decode_hostname, decode_rank
+        raise ValueError(f"Request id {request_id} does not contain hostname and decode_kv_rank")
+
+    def _send(self, hostname: str, port: int, request_id: str, keys: torch.Tensor, values: torch.Tensor, hidden: torch.Tensor):
+        remote_address = f"{hostname}:{port}"
+        self.data_plane.send_tensor(keys, f"{request_id}_keys", remote_address)
+        self.data_plane.send_tensor(values, f"{request_id}_values", remote_address)
+        self.data_plane.send_tensor(hidden, f"{request_id}_hidden", remote_address)
+
+    def _recv(self, request_id: str) -> Tuple[torch.Tensor, torch.Tensor, torch.Tensor]:
+        keys = self.data_plane.recv_tensor(f"{request_id}_keys")
+        values = self.data_plane.recv_tensor(f"{request_id}_values")
+        hidden = self.data_plane.recv_tensor(f"{request_id}_hidden")
+        return keys, values, hidden
+
+    def _get_kv_group_rank(self, kv_rank: int, rank: int, config: KVTransferConfig) -> int:
+        if kv_rank < config.kv_producers_parallel_size:
+            return kv_rank
+        
+        kv_consumer_rank = kv_rank - config.kv_producers_parallel_size
+        return config.kv_producers_parallel_size + kv_consumer_rank * config.tensor_parallel_multiplier + rank % config.tensor_parallel_multiplier
+    
+
+    def _get_global_kv_rank(self, kv_rank: int, rank: int, config: KVTransferConfig) -> int:
+        if kv_rank <= config.kv_producers_parallel_size:
+            return kv_rank * config.kv_producers_tensor_parallel_size + rank
+        
+        kv_consumer_rank = kv_rank - config.kv_producers_parallel_size
+        return config.kv_producers_parallel_size * config.kv_producers_tensor_parallel_size + kv_consumer_rank * config.kv_consumers_tensor_parallel_size + rank
+
+
+    def _get_data_plane_port(self, global_kv_rank: int) -> int:
+        return self.config.kv_port + self.config.kv_producers_tensor_parallel_size + 1 + global_kv_rank
+
+    def _broadcast_and_enhance_kv_config(self, rank: int, config: VllmConfig, world_group):
+        if rank == 0:
+            config_group = StatelessProcessGroup.create(
+                host=self.config.kv_ip,
+                port=self.config.kv_port,
+                rank=self.config.kv_rank,
+                world_size=self.config.kv_parallel_size,
+            )
+            parallel_configs = config_group.all_gather_obj({
+                "kv_role": self.config.kv_role,
+                "tensor_parallel_size": config.parallel_config.tensor_parallel_size,
+                "pipeline_parallel_size": config.parallel_config.pipeline_parallel_size,
+            })
+            logger.debug("parallel_configs: %s", parallel_configs)
+            kv_config_enhanced = {
+                "kv_producers_tensor_parallel_size": None,
+                "kv_consumers_tensor_parallel_size": None,
+                "kv_producers_pipeline_parallel_size": None,
+                "kv_consumers_pipeline_parallel_size": None,
+                "kv_producers_parallel_size": 0,
+            }
+            for parallel_config in parallel_configs:
+                kv_role = parallel_config["kv_role"]
+                assert parallel_config["pipeline_parallel_size"] == 1, f"Only pipeline parallel size 1 is supported for kv transfer instances"
+                
+                if kv_role == "kv_producer":
+                    kv_config_enhanced["kv_producers_parallel_size"] += 1
+                if kv_config_enhanced[f"{kv_role}s_tensor_parallel_size"] is None:
+                    kv_config_enhanced[f"{kv_role}s_tensor_parallel_size"] = parallel_config["tensor_parallel_size"]
+                    kv_config_enhanced[f"{kv_role}s_pipeline_parallel_size"] = parallel_config["pipeline_parallel_size"]
+                else:
+                    assert kv_config_enhanced[f"{kv_role}s_tensor_parallel_size"] == parallel_config["tensor_parallel_size"], f"All kv {kv_role}s should have the same tensor parallel size"
+                    assert kv_config_enhanced[f"{kv_role}s_pipeline_parallel_size"] == parallel_config["pipeline_parallel_size"], f"All kv {kv_role}s should have the same pipeline parallel size"
+            world_group.broadcast_object(kv_config_enhanced)
+        else:
+            kv_config_enhanced = world_group.broadcast_object()
+        logger.info("kv_config_enhanced: %s", kv_config_enhanced)
+
+        self.config.kv_producers_tensor_parallel_size = kv_config_enhanced["kv_producers_tensor_parallel_size"]
+        self.config.kv_consumers_tensor_parallel_size = kv_config_enhanced["kv_consumers_tensor_parallel_size"]
+        self.config.kv_producers_pipeline_parallel_size = kv_config_enhanced["kv_producers_pipeline_parallel_size"]
+        self.config.kv_consumers_pipeline_parallel_size = kv_config_enhanced["kv_consumers_pipeline_parallel_size"]
+        self.config.kv_producers_parallel_size = kv_config_enhanced["kv_producers_parallel_size"]
\ No newline at end of file
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
diff --git a/vllm/distributed/kv_transfer/kv_lookup_buffer/simple_buffer.py b/vllm/distributed/kv_transfer/kv_lookup_buffer/simple_buffer.py
index 5e1b6235..b4506877 100644
--- a/vllm/distributed/kv_transfer/kv_lookup_buffer/simple_buffer.py
+++ b/vllm/distributed/kv_transfer/kv_lookup_buffer/simple_buffer.py
@@ -12,7 +12,8 @@
 import threading
 import time
 from collections import deque
-from typing import Deque, List, Optional, Union
+from concurrent.futures import ThreadPoolExecutor
+from typing import Deque, List, Optional, Union, Dict
 
 import torch
 
@@ -46,7 +47,7 @@ class SimpleBuffer(KVLookupBufferBase):
         self.buffer_lock = threading.Lock()
         self.signal_pipe = signal_pipe
         self.data_pipe = data_pipe
-        self.request_handling_thread: Optional[threading.Thread] = None
+        self.request_handling_thread: Optional[ThreadPoolExecutor] = None
 
         self.normal_signal = torch.tensor([0], device="cpu")
         self.end_signal = None
@@ -57,10 +58,16 @@ class SimpleBuffer(KVLookupBufferBase):
         # tokens_roi_sender: tokens and roi of the producer (in the buffer)
         # tokens_roi_recver: tokens and roi of the consumer (query)
 
-        tokens_sender = tokens_roi_sender[0]
-        tokens_recver = tokens_roi_recver[0]
-        roi_sender = tokens_roi_sender[1]
-        roi_recver = tokens_roi_recver[1]
+        target_rank_sender = tokens_roi_sender[0]
+        target_rank_recver = tokens_roi_recver[0]
+
+        if target_rank_sender.item() != target_rank_recver.item():
+            return 0
+        
+        tokens_sender = tokens_roi_sender[1]
+        tokens_recver = tokens_roi_recver[1]
+        roi_sender = tokens_roi_sender[2]
+        roi_recver = tokens_roi_recver[2]
 
         if tokens_recver is None:
             # consumer sends an empty request
@@ -80,14 +87,14 @@ class SimpleBuffer(KVLookupBufferBase):
 
         return 0
 
-    def _send_tensor_and_dec_size(self,
-                                  tensor: Optional[torch.Tensor]) -> None:
+    def _send_tensor_and_dec_size(self, tensor: Optional[torch.Tensor],
+                                  target_rank: int) -> None:
 
         assert tensor is not None, "Use self.data_pipe.send(None) instead"
         self.buffer_size -= tensor.element_size() * tensor.numel()
         if tensor.dtype == torch.bool:
             tensor = tensor.float()
-        self.data_pipe.send_tensor(tensor)
+        self.data_pipe.send_tensor(tensor, target_rank)
 
     def _get_element_size(self, data: Optional[Union[List, torch.Tensor]]):
 
@@ -100,7 +107,7 @@ class SimpleBuffer(KVLookupBufferBase):
 
         raise AssertionError(f"Unknown data type {type(data)}")
 
-    def _add_to_buffer(self, input_tokens: torch.Tensor, roi: torch.Tensor,
+    def _add_to_buffer(self, target_rank: int, input_tokens: torch.Tensor, roi: torch.Tensor,
                        key: torch.Tensor, value: torch.Tensor,
                        hidden: torch.Tensor):
 
@@ -115,7 +122,7 @@ class SimpleBuffer(KVLookupBufferBase):
         if isinstance(hidden, torch.Tensor):
             hidden = hidden.clone()
 
-        buffer_item = [input_tokens, roi, key, value, hidden]
+        buffer_item = [torch.tensor(target_rank), input_tokens, roi, key, value, hidden]
 
         with self.buffer_lock:
             for data in buffer_item:
@@ -125,53 +132,54 @@ class SimpleBuffer(KVLookupBufferBase):
     def _is_end_signal(self, signal):
         return signal is None
 
-    def drop_select_handler(self):
+    def drop_select_handler(self, rank: int):
 
         try:
 
-            while True:
-                signal = self.signal_pipe.recv_tensor()
-                if self._is_end_signal(signal):
-                    logger.info("Received end signal!")
-                    break
-
-                input_tokens = self.data_pipe.recv_tensor()
-
-                roi = self.data_pipe.recv_tensor()
-                assert roi is not None, "Please provide the roi when sending "\
-                    "drop-select request"
-                roi = (roi > 0.5)
-                tokens_roi_recver = [input_tokens, roi]
-
-                matched_length = 0
-
-                # perform input tokens and roi matching
-                # FIXME: this matching is O(n), ideally it should be O(1)
-                # but this buffer size won't (and shouldn't) be too large so
-                # the fix is not urgent.
-                with self.buffer_lock:
-
-                    for _ in range(len(self.buffer)):
-
-                        temp_length = self._matches(self.buffer[0],
-                                                    tokens_roi_recver)
-                        if temp_length > 0:
-                            matched_length = temp_length
-                            break
-                        # rotate the element we just accessed to the end
-                        self.buffer.rotate(-1)
-
-                    if matched_length > 0:
-                        # need to clone the tensor
-                        # in case the tensor is freed before sending finishes
-                        matched_item = self.buffer.popleft()
-                        for tensor in matched_item:
-                            self._send_tensor_and_dec_size(tensor)
-
-                    else:
-                        # no match, just send None
-                        for _ in range(5):
-                            self.data_pipe.send_tensor(None)
+            signal = self.signal_pipe.recv_tensor(rank)
+            if self._is_end_signal(signal):
+                logger.info("Received end signal!")
+                return
+            target_kv_rank = self.data_pipe.recv_tensor(rank)
+            # assert target_rank.item() == rank, "Target rank does not match"\
+            #     "the rank of the drop-select handler"
+            input_tokens = self.data_pipe.recv_tensor(rank)
+            roi = self.data_pipe.recv_tensor(rank)
+            assert roi is not None, "Please provide the roi when sending "\
+                "drop-select request"
+            roi = (roi > 0.5)
+            tokens_roi_recver = [target_kv_rank, input_tokens, roi]
+
+            matched_length = 0
+
+            # perform input tokens and roi matching
+            # FIXME: this matching is O(n), ideally it should be O(1)
+            # but this buffer size won't (and shouldn't) be too large so
+            # the fix is not urgent.
+            with self.buffer_lock:
+
+                for _ in range(len(self.buffer)):
+
+                    temp_length = self._matches(self.buffer[0],
+                                                tokens_roi_recver)
+                    if temp_length > 0:
+                        matched_length = temp_length
+                        break
+                    # rotate the element we just accessed to the end
+                    self.buffer.rotate(-1)
+
+                if matched_length > 0:
+                    # need to clone the tensor
+                    # in case the tensor is freed before sending finishes
+                    matched_item = self.buffer.popleft()
+                    target_rank = matched_item[0].item()
+                    for tensor in matched_item[1:]:
+                        self._send_tensor_and_dec_size(tensor, rank)
+
+                else:
+                    # no match, just send None
+                    for _ in range(5):
+                        self.data_pipe.send_tensor(None, rank)
 
         except RuntimeError as e:
             if 'Connection closed by peer' not in str(e):
@@ -180,10 +188,10 @@ class SimpleBuffer(KVLookupBufferBase):
         logger.debug("Closing drop_select_handler")
 
     def drop_select(
-            self, input_tokens: Optional[torch.Tensor],
+            self, rank: int, kv_rank: int, input_tokens: Optional[torch.Tensor],
             roi: Optional[torch.Tensor]) -> List[Optional[torch.Tensor]]:
 
-        assert self.request_handling_thread is None, \
+        assert not self.request_handling_thread, \
             "drop_select should be called by the KV cache consumer "\
             "(e.g. the decode vLLM instance)"
 
@@ -192,26 +200,28 @@ class SimpleBuffer(KVLookupBufferBase):
         if isinstance(roi, torch.Tensor):
             roi = roi.clone().float()
 
-        self.signal_pipe.send_tensor(self.normal_signal)
-        self.data_pipe.send_tensor(input_tokens)
-        self.data_pipe.send_tensor(roi)
+        self.signal_pipe.send_tensor(self.normal_signal, rank)
+
+        self.data_pipe.send_tensor(torch.tensor(kv_rank), rank)
+        self.data_pipe.send_tensor(input_tokens, rank)
+        self.data_pipe.send_tensor(roi, rank)
 
-        input_tokens = self.data_pipe.recv_tensor()
-        roi = self.data_pipe.recv_tensor()
+        input_tokens = self.data_pipe.recv_tensor(rank)
+        roi = self.data_pipe.recv_tensor(rank)
         if roi is not None:
             # convert from float tensor to bool tensor
             # as PyNccl does not support sending bool tensor
             roi = (roi > 0.5)
-        key = self.data_pipe.recv_tensor()
-        value = self.data_pipe.recv_tensor()
-        hidden = self.data_pipe.recv_tensor()
+        key = self.data_pipe.recv_tensor(rank)
+        value = self.data_pipe.recv_tensor(rank)
+        hidden = self.data_pipe.recv_tensor(rank)
 
         return [input_tokens, roi, key, value, hidden]
 
     def full_handler(self):
         time.sleep(0.001)
 
-    def insert(self, input_tokens: torch.Tensor, roi: torch.Tensor,
+    def insert(self, kv_group_rank: int, target_rank: int, input_tokens: torch.Tensor, roi: torch.Tensor,
                key: torch.Tensor, value: torch.Tensor,
                hidden: torch.Tensor) -> None:
 
@@ -222,20 +232,19 @@ class SimpleBuffer(KVLookupBufferBase):
         while self.buffer_size > self.buffer_size_threshold:
             self.full_handler()
 
-        self._add_to_buffer(input_tokens, roi, key, value, hidden)
+        self._add_to_buffer(target_rank, input_tokens, roi, key, value, hidden)
 
         # when calling the insert, the current process is a sender
         # need to launch the request handler and start listening to request.
+        target_rank_global = target_rank + kv_group_rank
         if self.request_handling_thread is None:
-            self.request_handling_thread = threading.Thread(
-                target=self.drop_select_handler)
-            self.request_handling_thread.start()
+            self.request_handling_thread = ThreadPoolExecutor(max_workers=1)
+        self.request_handling_thread.submit(self.drop_select_handler, target_rank_global)
 
     def close(self):
 
-        if hasattr(self, "request_handling_thread"
-                   ) and self.request_handling_thread is not None:
-            self.request_handling_thread.join()
+        if hasattr(self, "request_handling_thread") and self.request_handling_thread:
+            self.request_handling_thread.shutdown()
 
         else:
             # TODO: have a explicit close signal and have a explicit way to
diff --git a/vllm/distributed/kv_transfer/kv_pipe/base.py b/vllm/distributed/kv_transfer/kv_pipe/base.py
index 40589fb3..da2829cf 100644
--- a/vllm/distributed/kv_transfer/kv_pipe/base.py
+++ b/vllm/distributed/kv_transfer/kv_pipe/base.py
@@ -23,7 +23,7 @@ class KVPipeBase(ABC):
     """
 
     @abstractmethod
-    def send_tensor(self, tensor: Optional[torch.Tensor]) -> None:
+    def send_tensor(self, tensor: Optional[torch.Tensor], target_rank: int = 0) -> None:
         """Send a tensor, or None, via the pipe.
         
         Need to support sending None -- important for error handling.
@@ -41,7 +41,7 @@ class KVPipeBase(ABC):
         raise NotImplementedError
 
     @abstractmethod
-    def recv_tensor(self) -> Optional[torch.Tensor]:
+    def recv_tensor(self, src_rank: int) -> Optional[torch.Tensor]:
         """Receive a tensor (can be None) from the pipeline.
 
         Returns:
diff --git a/vllm/distributed/kv_transfer/kv_pipe/pynccl_pipe.py b/vllm/distributed/kv_transfer/kv_pipe/pynccl_pipe.py
1869
index 7aa53d07..f5dd50b7 100644
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
1921
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
--- a/vllm/distributed/kv_transfer/kv_pipe/pynccl_pipe.py
+++ b/vllm/distributed/kv_transfer/kv_pipe/pynccl_pipe.py
@@ -45,33 +45,33 @@ class PyNcclPipe(KVPipeBase):
     METADATA_DTYPE = torch.int64
 
     def __init__(self,
+                 kv_group_rank: int,
                  local_rank: int,
                  config: KVTransferConfig,
                  device: Optional[str] = None,
                  port_offset: int = 0):
         self.config = config
         self.local_rank = local_rank
-        self.kv_rank = self.config.kv_rank
+        self.kv_group_rank = kv_group_rank
         self.kv_parallel_size = self.config.kv_parallel_size
+        self.kv_world_size = self.config.kv_world_size
         if device is None:
             self.device = self._select_device(self.config.kv_buffer_device)
         else:
             self.device = self._select_device(device)
 
         # build distributed connection and send/recv implementation
+        logger.info("Creating process group for kv transfer with rank %d and world size %d, ip: %s, port: %d", self.kv_group_rank, self.kv_world_size, self.config.kv_ip, self.config.kv_port + port_offset)
         self.group = StatelessProcessGroup.create(
             host=self.config.kv_ip,
             port=self.config.kv_port + port_offset,
-            rank=self.kv_rank,
-            world_size=self.kv_parallel_size,
+            rank=self.kv_group_rank,
+            world_size=self.kv_world_size,
         )
         # add a barrier to make sure the connection is initiated properly
         self.group.barrier()
         impl = self._get_device_send_recv_impl(self.group)
         self.device_send_func, self.device_recv_func = impl
-        # set target rank
-        self.target_rank_for_send = (self.kv_rank + 1) % self.kv_parallel_size
-        self.target_rank_for_recv = (self.kv_rank - 1) % self.kv_parallel_size
 
         # transportation-related variables
         self.transport_thread: Optional[ThreadPoolExecutor] = None
@@ -145,16 +145,16 @@ class PyNcclPipe(KVPipeBase):
                            dtype=metadata["dtype"],
                            device=self.device)
 
-    def _send_metadata(self, metadata: Metadata):
+    def _send_metadata(self, metadata: Metadata, target_rank: int):
         """
         Send the metadata dictionary to the target rank.
 
         Parameters:
             - metadata: A dictionary with keys "dtype" and "shape".
         """
-        self.group.send_obj(metadata, self.target_rank_for_send)
+        self.group.send_obj(metadata, target_rank)
 
-    def _recv_metadata(self) -> Metadata:
+    def _recv_metadata(self, src_rank: int) -> Metadata:
         """
         Receive the metadata dictionary from the target rank.
 
@@ -162,9 +162,9 @@ class PyNcclPipe(KVPipeBase):
             - metadata: A dictionary with keys "dtype" and "shape" describing 
               the tensor.
         """
-        return self.group.recv_obj(self.target_rank_for_recv)
+        return self.group.recv_obj(src_rank)
 
-    def _send_impl(self, tensor: Optional[torch.Tensor]) -> None:
+    def _send_impl(self, tensor: Optional[torch.Tensor], target_rank: int) -> None:
         """
         The actual implementation of sending the tensor and its metadata to the 
         target rank.
@@ -174,12 +174,12 @@ class PyNcclPipe(KVPipeBase):
               being sent.
         """
         metadata = self._make_metadata(tensor)
-        self._send_metadata(metadata)
+        self._send_metadata(metadata, target_rank)
         if tensor is not None:
             self.device_send_func(tensor.to(self.device),
-                                  self.target_rank_for_send)
+                                  target_rank)
 
-    def _recv_impl(self) -> Optional[torch.Tensor]:
+    def _recv_impl(self, src_rank: int) -> Optional[torch.Tensor]:
         """
         The actual implementation of receiving a tensor and its metadata from 
         the target rank.
@@ -187,21 +187,22 @@ class PyNcclPipe(KVPipeBase):
         Returns:
             - buffer: The received tensor, or None if no tensor is received.
         """
-        metadata = self._recv_metadata()
+        metadata = self._recv_metadata(src_rank)
         if metadata["dtype"] is None:
             return None
         buffer = self._prepare_recv_buffer(metadata)
-        self.device_recv_func(buffer, self.target_rank_for_recv)
+        self.device_recv_func(buffer, src_rank)
 
         return buffer
 
     def send_tensor_wrapper(self, tensor: Optional[torch.Tensor],
-                            tensor_size: int) -> None:
+                            tensor_size: int,
+                            target_rank: int) -> None:
         """
         Wrapper for _send_impl to handle exceptions and update buffer size.
         """
         try:
-            self._send_impl(tensor)
+            self._send_impl(tensor, target_rank)
 
             with self.buffer_size_lock:
                 self.buffer_size -= tensor_size
@@ -220,7 +221,7 @@ class PyNcclPipe(KVPipeBase):
             logger.debug("KV cache transfer pipe is full. Waiting...")
             time.sleep(0.05)
 
-    def send_tensor(self, tensor: Optional[torch.Tensor]) -> None:
+    def send_tensor(self, tensor: Optional[torch.Tensor], target_rank: int) -> None:
         """
         Sends a tensor and its metadata to the destination rank in a 
         non-blocking way.
@@ -228,6 +229,7 @@ class PyNcclPipe(KVPipeBase):
         Parameters:
             - tensor: The tensor to send, or None if no tensor is being sent.
         """
+        logger.debug("Rank %d sending tensor of shape %s dtype %s to rank %d", self.kv_group_rank, tensor.shape if tensor is not None else "None", tensor.dtype if tensor is not None else "None", target_rank)
         if self.transport_thread is None:
             self.transport_thread = ThreadPoolExecutor(max_workers=1)
 
2004
2005
@@ -241,32 +243,39 @@ class PyNcclPipe(KVPipeBase):
         with self.buffer_size_lock:
2006
2007
             self.buffer_size += tensor_size
 
2008
-        self.transport_thread.submit(self.send_tensor_wrapper, tensor,
2009
-                                     tensor_size)
2010
+        future = self.transport_thread.submit(self.send_tensor_wrapper, tensor,
2011
2012
+                                     tensor_size,
+                                     target_rank)
2013
+        return future
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
2031
 
-    def recv_tensor(self) -> Optional[torch.Tensor]:
+    def recv_tensor(self, src_rank: int) -> Optional[torch.Tensor]:
         """
         Receives a tensor and its metadata from the source rank. Blocking call.
 
         Returns:
             - tensor: The received tensor, or None if no tensor is received.
         """
+
+        logger.debug("Rank %d receiving tensor from rank %d", self.kv_group_rank, src_rank)
+
         if self.transport_thread is None:
             self.transport_thread = ThreadPoolExecutor(max_workers=1)
 
-        future = self.transport_thread.submit(self._recv_impl)
+        future = self.transport_thread.submit(self._recv_impl, src_rank)
 
2032
2033
2034
2035
2036
2037
2038
2039
2040
2041
2042
2043
2044
2045
2046
2047
2048
2049
2050
2051
2052
2053
2054
2055
2056
2057
-        try:
-            tensor = future.result()
-        except Exception as e:
-            logger.error("Encountering exception in KV receiving thread")
-            logger.error("%s", e)
-            logger.error("My device: %s", self.device)
-            import traceback
-            traceback.print_exc()
-            raise e
+        return future
+
+        # try:
+        #     tensor = future.result()
+        # except Exception as e:
+        #     logger.error("Encountering exception in KV receiving thread")
+        #     logger.error("%s", e)
+        #     logger.error("My device: %s", self.device)
+        #     import traceback
+        #     traceback.print_exc()
+        #     raise e
 
-        return tensor
+        # return tensor
 
     def close(self):
         """
2058
diff --git a/vllm/distributed/kv_transfer/kv_pipe/dynemo_nccl_pipe.py b/vllm/distributed/kv_transfer/kv_pipe/dynemo_nccl_pipe.py
2059
2060
2061
new file mode 100644
index 00000000..8a356504
--- /dev/null
2062
+++ b/vllm/distributed/kv_transfer/kv_pipe/dynemo_nccl_pipe.py
2063
2064
2065
2066
2067
2068
2069
2070
2071
2072
2073
2074
2075
2076
2077
@@ -0,0 +1,124 @@
+import logging
+import threading
+import typing
+import zmq
+import socket
+import time
+import torch
+
+from vllm.distributed.kv_transfer.kv_pipe.pynccl_pipe import PyNcclPipe
+
+
+logger = logging.getLogger(__name__)
+
+
2078
+class DynemoNcclDataPlane:
2079
2080
2081
2082
2083
2084
2085
2086
2087
2088
2089
2090
2091
2092
2093
2094
2095
2096
2097
2098
2099
2100
2101
2102
2103
2104
2105
2106
2107
2108
2109
2110
2111
2112
2113
2114
2115
2116
2117
2118
2119
2120
2121
2122
2123
2124
2125
2126
2127
2128
2129
2130
2131
2132
2133
2134
2135
2136
2137
2138
2139
2140
2141
2142
2143
2144
2145
2146
2147
2148
2149
2150
2151
2152
2153
2154
2155
2156
2157
2158
2159
2160
2161
2162
2163
2164
2165
2166
2167
2168
2169
2170
2171
2172
2173
2174
2175
2176
2177
2178
2179
2180
2181
2182
2183
2184
2185
2186
2187
+    def __init__(
+        self,
+        data_pipe: PyNcclPipe,
+        hostname: str = "",
+        port: int = 0,
+    ) -> None:
+        
+        self.data_pipe = data_pipe
+        if not hostname:
+            hostname = socket.gethostname()
+        if port == 0:
+            raise ValueError("Port cannot be 0")
+        self._hostname = hostname
+        self._port = port
+        self.store = {}
+        self.context = zmq.Context()
+        self.rep_socket = self.context.socket(zmq.REP)
+        logger.info(f"Rank {self.rank} binding to {self._hostname}:{self._port}")
+        self.rep_socket.bind(f"tcp://{self._hostname}:{self._port}")
+        self._listener_thread = threading.Thread(target=self.listen_for_requests, daemon=True)
+        self._listener_thread.start()
+        self.req_sockets = {}
+        logger.info(f"Rank {self.rank} connected to the server")
+
+    @property
+    def rank(self):
+        return self.data_pipe.kv_group_rank
+    
+    def send_tensor(
+        self,
+        tensor: torch.Tensor,
+        tensor_id: str,
+        remote_address: typing.Optional[str] = None,
+    ):
+        logger.debug(f"Rank {self.rank} sending tensor {tensor_id} to {remote_address}")
+        return self._send_tensor(tensor, tensor_id, remote_address)
+
+    def recv_tensor(
+        self,
+        tensor_id: str,
+        remote_address: typing.Optional[str] = None,
+    ) -> torch.Tensor:
+        ret = self._recv_tensor(tensor_id, remote_address)
+        return ret
+
+    def _send_tensor(
+        self,
+        tensor: torch.Tensor,
+        tensor_id: str,
+        remote_address: typing.Optional[str] = None,
+    ):
+        logger.debug(f"Rank {self.rank} storing tensor with id {tensor_id} of shape {tensor.shape} and dtype {tensor.dtype}")
+        if remote_address is None:
+            self.store[tensor_id] = tensor
+        else:
+            # tensor_shape = "_".join(str(dim) for dim in tensor.shape)
+            # tensor_dtype = str(tensor.dtype)
+            if remote_address not in self.req_sockets:
+                self.req_sockets[remote_address] = self.context.socket(zmq.REQ)
+                self.req_sockets[remote_address].connect(f"tcp://{remote_address}")
+
+            req_socket = self.req_sockets[remote_address]
+            # req_socket.connect(f"tcp://{remote_address}")
+            req_socket.send_string(f"PUT {self.rank} {tensor_id}")
+            dst_rank = req_socket.recv_string()
+            logger.debug(f"Rank {self.rank} sending tensor {tensor_id} to rank {dst_rank}")
+            self.data_pipe.send_tensor(tensor, int(dst_rank))
+
+    def _recv_tensor(
+        self,
+        tensor_id: str,
+        remote_address: typing.Optional[str] = None,
+    ) -> torch.Tensor:
+        logger.debug(f"Rank {self.rank} receiving tensor")
+        if remote_address is not None:
+            raise NotImplementedError("Getting tensor from remote rank not implemented")
+        if tensor_id in self.store:
+            logger.debug(f"Popping tensor {tensor_id} from store")
+            future = self.store.pop(tensor_id)
+            tensor = future.result() # TODO ptarasiewicz we should run other request instead of wait
+            logger.debug(f"Rank {self.rank} received tensor")
+            return tensor
+            
+        logger.debug(f"Rank {self.rank} waiting for tensor {tensor_id}")
+        time.sleep(0.001)
+        return self._recv_tensor(tensor_id, remote_address)
+        # raise NotImplementedError("Tensor not found in store")
+
+    def _receive_tensor(
+        self,
+        tensor_id: str,
+        rank: int,
+    ):
+        future = self.data_pipe.recv_tensor(rank)
+        logger.debug(f"Rank {self.rank} storing tensor {tensor_id} in store")
+        self.store[tensor_id] = future
+
+    def listen_for_requests(self):
+        while True:
+            cmd, rank, tensor_id = self.rep_socket.recv_string().split()
+            logger.debug(f"Rank {self.rank} received request for tensor {tensor_id}")
+            self.rep_socket.send_string(f"{self.rank}")
+            if cmd == "GET":
+                raise NotImplementedError("Getting tensor from remote rank not implemented")
+            elif cmd == "PUT":
+                rank = int(rank)
+                # shape = [int(dim) for dim in shape.split("_")]
+                # dtype = getattr(torch, dtype)
+                self._receive_tensor(tensor_id, rank)
2188
2189
2190
2191
2192
2193
2194
2195
2196
2197
2198
2199
2200
2201
2202
2203
2204
2205
2206
2207
2208
2209
2210
2211
2212
2213
2214
2215
2216
2217
2218
2219
2220
2221
2222
diff --git a/vllm/distributed/kv_transfer/kv_transfer_agent.py b/vllm/distributed/kv_transfer/kv_transfer_agent.py
index 1e80e0bd..cd90206f 100644
--- a/vllm/distributed/kv_transfer/kv_transfer_agent.py
+++ b/vllm/distributed/kv_transfer/kv_transfer_agent.py
@@ -35,6 +35,7 @@ class KVTransferAgent:
         rank: int,
         local_rank: int,
         config: "VllmConfig",
+        world_group,
     ):
 
         self.config = config
@@ -47,7 +48,7 @@ class KVTransferAgent:
             "TransferAgent should only be used when kv_connector is set."
 
         self.connector = KVConnectorFactory.create_connector(
-            rank, local_rank, config)
+            rank, local_rank, config, world_group)
 
     def send_kv_caches_and_hidden_states(
         self,
diff --git a/vllm/distributed/parallel_state.py b/vllm/distributed/parallel_state.py
index 321902d1..b8937ef8 100644
--- a/vllm/distributed/parallel_state.py
+++ b/vllm/distributed/parallel_state.py
@@ -1085,7 +1085,8 @@ def ensure_kv_transfer_initialized(vllm_config: "VllmConfig") -> None:
         _KV_TRANSFER = kv_transfer.KVTransferAgent(
             rank=get_world_group().rank,
             local_rank=get_world_group().local_rank,
-            config=vllm_config)
+            config=vllm_config,
+            world_group=get_world_group())
 
 
 def ensure_model_parallel_initialized(
2223
diff --git a/vllm/engine/llm_engine.py b/vllm/engine/llm_engine.py
2224
index d82d9ad9..9ba1a326 100644
2225
2226
--- a/vllm/engine/llm_engine.py
+++ b/vllm/engine/llm_engine.py
ptarasiewiczNV's avatar
ptarasiewiczNV committed
2227
2228
2229
2230
2231
2232
2233
2234
2235
2236
2237
2238
2239
2240
2241
2242
2243
2244
2245
2246
2247
2248
2249
2250
2251
2252
2253
2254
2255
2256
2257
2258
2259
2260
2261
2262
2263
2264
2265
2266
2267
2268
2269
2270
2271
2272
2273
2274
2275
2276
2277
2278
2279
2280
2281
2282
2283
2284
2285
2286
2287
2288
2289
2290
2291
2292
@@ -2,13 +2,17 @@
 
 import copy
 import time
+import pickle
+import uuid
 from collections import Counter as collectionsCounter
 from collections import deque
+from collections import defaultdict
 from contextlib import contextmanager
 from dataclasses import dataclass
+from concurrent.futures import ThreadPoolExecutor
 from functools import partial
 from typing import (TYPE_CHECKING, Callable, ClassVar, Deque, Dict, Iterable,
-                    List, Mapping, NamedTuple, Optional)
+                    List, Mapping, NamedTuple, Optional, Tuple)
 from typing import Sequence as GenericSequence
 from typing import Set, Type, Union, cast, overload
 
@@ -60,6 +64,9 @@ from vllm.usage.usage_lib import (UsageContext, is_usage_stats_enabled,
                                   usage_message)
 from vllm.utils import Counter, Device, deprecate_kwargs, weak_bind
 from vllm.version import __version__ as VLLM_VERSION
+from vllm.remote_prefill import RemotePrefillRequest, RemotePrefillParams, MemoryTransferRequest
+from vllm.distributed.device_communicators.nixl import NixlMetadata
+
 
 logger = init_logger(__name__)
 _LOCAL_LOGGING_INTERVAL_SEC = 5
@@ -90,7 +97,7 @@ class OutputData(NamedTuple):
     # outputs from multiple steps.
     is_first_step_output: Optional[bool]
     skip: List[int]
-
+    remote_prefill_requests: Optional[List[RemotePrefillRequest]]
 
 class SchedulerContext:
 
@@ -104,11 +111,14 @@ class SchedulerContext:
 
         self.multi_step_stream_outputs: bool = multi_step_stream_outputs
 
+        self.remote_prefill_requests: List[RemotePrefillRequest] = []
+
     def append_output(self, outputs: List[SamplerOutput],
                       seq_group_metadata_list: List[SequenceGroupMetadata],
                       scheduler_outputs: SchedulerOutputs, is_async: bool,
                       is_last_step: bool,
-                      is_first_step_output: Optional[bool]):
+                      is_first_step_output: Optional[bool],
+                      remote_prefill_requests: Optional[List[RemotePrefillRequest]] = None):
         self.output_queue.append(
             OutputData(outputs=outputs,
                        seq_group_metadata_list=seq_group_metadata_list,
@@ -116,7 +126,9 @@ class SchedulerContext:
                        is_async=is_async,
                        is_last_step=is_last_step,
                        is_first_step_output=is_first_step_output,
-                       skip=[]))
+                       skip=[],
+                       remote_prefill_requests=remote_prefill_requests))
+
 
 
 class LLMEngine:
@@ -348,7 +360,7 @@ class LLMEngine:
2293
2294
2295
2296
2297
2298
2299
2300
         # GPU and CPU blocks, which are profiled in the distributed executor.
         self.scheduler = [
             Scheduler(
-                self.scheduler_config, self.cache_config, self.lora_config,
+                self.model_config, self.scheduler_config, self.cache_config, self.lora_config,
                 self.parallel_config.pipeline_parallel_size,
                 self.async_callbacks[v_id]
                 if self.model_config.use_async_output_proc else None)
ptarasiewiczNV's avatar
ptarasiewiczNV committed
2301
2302
2303
2304
2305
2306
@@ -405,6 +417,39 @@ class LLMEngine:
 
         self.seq_id_to_seq_group: Dict[str, SequenceGroupBase] = {}
 
+        self.engine_id = str(uuid.uuid4())
+        self._nixl_agents_names: Optional[List[str]] = None
2307
+        if self.vllm_config.kv_transfer_config is not None and self.vllm_config.kv_transfer_config.kv_connector == "DynemoNixlConnector":
ptarasiewiczNV's avatar
ptarasiewiczNV committed
2308
2309
2310
2311
2312
2313
2314
2315
2316
2317
2318
2319
2320
2321
2322
2323
2324
2325
2326
2327
2328
2329
+            self._nixl_agents_names = self._initialize_nixl()
+
+        self._request_notif_counter = defaultdict(lambda: -self.parallel_config.tensor_parallel_size)
+        self._finished_prefills = set()
+
+    @property
+    def is_nixl_initialized(self) -> bool:
+        return self._nixl_agents_names is not None
+
+    def get_nixl_metadata(self) -> NixlMetadata:
+        if not self.is_nixl_initialized:
+            raise RuntimeError("Nixl is not initialized")
+        agent_metadata = self.model_executor.collective_rpc("get_nixl_agent_metadata")
+        kv_caches_base_addr = self.model_executor.collective_rpc("get_nixl_kv_caches_base_addr")
+        return NixlMetadata(engine_id=self.engine_id, agent_metadata=agent_metadata, kv_caches_base_addr=kv_caches_base_addr)
+    
+    def add_remote_nixl_metadata(self, nixl_metadata: NixlMetadata) -> List[str]:
+        if not self.is_nixl_initialized:
+            raise RuntimeError("Nixl is not initialized")
+        engine_id = nixl_metadata.engine_id
+        agents_metadata = nixl_metadata.agent_metadata
+        kv_caches_base_addr = nixl_metadata.kv_caches_base_addr
2330
2331
+        if len(agents_metadata) != len(self._nixl_agents_names):
+            raise ValueError("Number of agents does not match. Make sure all engines are initialized with the same parallel sizes.")
ptarasiewiczNV's avatar
ptarasiewiczNV committed
2332
2333
2334
2335
2336
2337
2338
2339
2340
2341
2342
2343
2344
2345
2346
2347
2348
2349
2350
2351
2352
2353
2354
2355
2356
2357
2358
2359
2360
2361
2362
2363
2364
+        return self.model_executor.collective_rpc("add_remote_nixl_metadata", args=(engine_id, agents_metadata, kv_caches_base_addr))
+
+    def _initialize_nixl(self) -> List[bytes]:
+        agents_names = self.model_executor.collective_rpc("initialize_nixl", args=(self.engine_id,))
+        return agents_names
+
     def _initialize_kv_caches(self) -> None:
         """Initialize the KV cache in the worker(s).
 
@@ -500,6 +545,8 @@ class LLMEngine:
         # Shutdown model executor when engine is garbage collected
         # Use getattr since __init__ can fail before the field is set
         if model_executor := getattr(self, "model_executor", None):
+            if self._nixl_agents_names:
+                model_executor.collective_rpc("shutdown_nixl")
             model_executor.shutdown()
 
     def get_tokenizer_group(
@@ -552,11 +599,14 @@ class LLMEngine:
         prompt_adapter_request: Optional[PromptAdapterRequest],
         trace_headers: Optional[Mapping[str, str]] = None,
         priority: int = 0,
+        remote_prefill_params: Optional[RemotePrefillParams] = None,
     ) -> Optional[SequenceGroup]:
         """Add a processed request to the engine's request pool.
         return the created sequence group.
         """
         if isinstance(params, SamplingParams) and params.n > 1:
+            if remote_prefill_params is not None:
+                raise ValueError("Remote prefill params are not supported for multi-step sampling")
             ParallelSampleSequenceGroup.add_request(
                 request_id,
                 self,
2365
@@ -584,7 +634,7 @@ class LLMEngine:
ptarasiewiczNV's avatar
ptarasiewiczNV committed
2366
2367
2368
2369
2370
2371
2372
2373
             encoder_inputs = None
 
         seq = Sequence(seq_id, decoder_inputs, block_size, eos_token_id,
-                       lora_request, prompt_adapter_request)
+                       lora_request, prompt_adapter_request, remote_prefill_params)
 
         encoder_seq = (None if encoder_inputs is None else Sequence(
             seq_id, encoder_inputs, block_size, eos_token_id, lora_request,
2374
@@ -601,8 +651,12 @@ class LLMEngine:
ptarasiewiczNV's avatar
ptarasiewiczNV committed
2375
2376
2377
2378
2379
2380
2381
2382
2383
2384
2385
2386
2387
                 trace_headers=trace_headers,
                 prompt_adapter_request=prompt_adapter_request,
                 encoder_seq=encoder_seq,
-                priority=priority)
+                priority=priority,
+                remote_prefill_params=remote_prefill_params,
+            )
         elif isinstance(params, PoolingParams):
+            if remote_prefill_params is not None:
+                raise ValueError("Remote prefill params are not supported for pooling")
             seq_group = self._create_sequence_group_with_pooling(
                 request_id,
                 seq,
2388
@@ -673,6 +727,7 @@ class LLMEngine:
ptarasiewiczNV's avatar
ptarasiewiczNV committed
2389
2390
2391
2392
2393
2394
2395
             trace_headers: Optional[Mapping[str, str]] = None,
             prompt_adapter_request: Optional[PromptAdapterRequest] = None,
             priority: int = 0,
+            remote_prefill_params: Optional[RemotePrefillParams] = None,
             *,
             inputs: Optional[PromptType] = None,  # DEPRECATED
     ) -> None:
2396
@@ -765,6 +820,7 @@ class LLMEngine:
ptarasiewiczNV's avatar
ptarasiewiczNV committed
2397
2398
2399
2400
2401
2402
2403
             prompt_adapter_request=prompt_adapter_request,
             trace_headers=trace_headers,
             priority=priority,
+            remote_prefill_params=remote_prefill_params,
         )
 
     def _validate_token_prompt(self, prompt: PromptType,
2404
@@ -799,6 +855,7 @@ class LLMEngine:
ptarasiewiczNV's avatar
ptarasiewiczNV committed
2405
2406
2407
2408
2409
2410
2411
         prompt_adapter_request: Optional[PromptAdapterRequest] = None,
         encoder_seq: Optional[Sequence] = None,
         priority: int = 0,
+        remote_prefill_params: Optional[RemotePrefillParams] = None,
     ) -> SequenceGroup:
         """Creates a SequenceGroup with SamplingParams."""
         max_logprobs = self.get_model_config().max_logprobs
2412
@@ -829,7 +886,9 @@ class LLMEngine:
ptarasiewiczNV's avatar
ptarasiewiczNV committed
2413
2414
2415
2416
2417
2418
2419
2420
2421
2422
             trace_headers=trace_headers,
             prompt_adapter_request=prompt_adapter_request,
             encoder_seq=encoder_seq,
-            priority=priority)
+            priority=priority,
+            remote_prefill_params=remote_prefill_params
+        )
 
         return seq_group
 
2423
@@ -995,11 +1054,11 @@ class LLMEngine:
ptarasiewiczNV's avatar
ptarasiewiczNV committed
2424
2425
2426
2427
2428
2429
2430
2431
2432
2433
2434
2435
2436
             # When we process only one request, no pop is required
             # (since later we will process all of the rest)
             (outputs, seq_group_metadata_list, scheduler_outputs, is_async,
-             is_last_step, is_first_step_output, skip) = ctx.output_queue[0]
+             is_last_step, is_first_step_output, skip, remote_prefill_requests) = ctx.output_queue[0]
         else:
             (outputs, seq_group_metadata_list, scheduler_outputs, is_async,
              is_last_step, is_first_step_output,
-             skip) = ctx.output_queue.popleft()
+             skip, remote_prefill_requests) = ctx.output_queue.popleft()
 
         # Sanity check
         assert len(seq_group_metadata_list) == len(
2437
@@ -1325,15 +1384,49 @@ class LLMEngine:
ptarasiewiczNV's avatar
ptarasiewiczNV committed
2438
2439
2440
2441
2442
2443
2444
2445
2446
2447
2448
2449
2450
2451
2452
2453
2454
2455
2456
 
         # Clear outputs for each new scheduler iteration
         ctx.request_outputs.clear()
+        ctx.remote_prefill_requests.clear()
 
         # Skip the scheduler if there are any remaining steps in the seq groups.
         # This ensures that the scheduler is only called again when the current
         # batch has completed.
+        remote_prefill_seq_group_metadata_list: List[SequenceGroupMetadata] = []
+        running_seq_group_metadata_list: List[SequenceGroupMetadata] = []
+        remote_prefill_scheduled_seq_groups: List[ScheduledSequenceGroup] = []
+        running_scheduled_seq_groups: List[ScheduledSequenceGroup] = []
+        
         if not self._has_remaining_steps(seq_group_metadata_list):
-            # Schedule iteration
+
             (seq_group_metadata_list, scheduler_outputs,
              allow_async_output_proc
-             ) = self.scheduler[virtual_engine].schedule()
2457
+             ) = self.scheduler[virtual_engine].schedule(self._finished_prefills)
ptarasiewiczNV's avatar
ptarasiewiczNV committed
2458
2459
2460
2461
2462
2463
2464
2465
2466
2467
2468
2469
2470
2471
2472
2473
2474
2475
2476
2477
2478
2479
2480
2481
2482
2483
2484
2485
2486
2487
2488
+            
+
+            # Separate remote prefill and running seq groups
+            for seq_group_metadata, scheduled_seq_group in zip(seq_group_metadata_list, scheduler_outputs.scheduled_seq_groups):
+                if seq_group_metadata.do_remote_prefill:
+                    remote_prefill_seq_group_metadata_list.append(seq_group_metadata)
+                    remote_prefill_scheduled_seq_groups.append(scheduled_seq_group)
+                else:
+                    running_seq_group_metadata_list.append(seq_group_metadata)
+                    running_scheduled_seq_groups.append(scheduled_seq_group)
+
+            seq_group_metadata_list = running_seq_group_metadata_list
+            scheduler_outputs.scheduled_seq_groups = running_scheduled_seq_groups
+            
+            # Send remote prefill requests before model execution
+            for seq_group_metadata, scheduled_seq_group in zip(remote_prefill_seq_group_metadata_list, remote_prefill_scheduled_seq_groups):
+                assert len(scheduled_seq_group.seq_group.seqs) == 1
+                assert self._nixl_agents_names
+                seq_id = scheduled_seq_group.seq_group.seqs[0].seq_id
+                block_table = seq_group_metadata.block_tables[seq_id]
+                remote_prefill_request = RemotePrefillRequest(
+                    request_id=seq_group_metadata.request_id,
+                    prompt_token_ids=scheduled_seq_group.seq_group.seqs[0].inputs.prompt_token_ids[:-1], # last one will be decoded on decode for sampling anyway
+                    sampling_params=scheduled_seq_group.seq_group.sampling_params,
+                    block_ids=block_table,
+                    engine_id=self.engine_id,
+                )
+                scheduled_seq_group.seq_group.remote_prefill_params.remote_prefill_request_callback(remote_prefill_request)
 
             ctx.seq_group_metadata_list = seq_group_metadata_list
             ctx.scheduler_outputs = scheduler_outputs
2489
@@ -1383,9 +1476,29 @@ class LLMEngine:
ptarasiewiczNV's avatar
ptarasiewiczNV committed
2490
2491
2492
2493
2494
2495
2496
2497
2498
2499
2500
2501
2502
2503
2504
2505
2506
2507
2508
2509
2510
2511
2512
2513
2514
                 execute_model_req.async_callback = self.async_callbacks[
                     virtual_engine]
 
-            outputs = self.model_executor.execute_model(
+            # After model execution, we need to transfer the memory from the prefill to the decode
+            memory_transfer_reqs = []
+            for scheduled_seq_group, seq_group_metadata in zip(scheduler_outputs.scheduled_seq_groups, seq_group_metadata_list):
+                remote_prefill_params = scheduled_seq_group.seq_group.remote_prefill_params
+                if remote_prefill_params is not None and remote_prefill_params.is_remote_decode:
+                    assert len(scheduled_seq_group.seq_group.seqs) == 1
+                    req_id = scheduled_seq_group.seq_group.request_id
+                    seq_id = scheduled_seq_group.seq_group.seqs[0].seq_id
+                    block_table = seq_group_metadata.block_tables[seq_id]
+                    memory_transfer_req = MemoryTransferRequest(
+                        request_id=req_id,
+                        src_block_ids=block_table,
+                        dst_block_ids=remote_prefill_params.decode_block_ids,
+                        dst_engine_id=remote_prefill_params.decode_engine_id,
+                        notify_msg=req_id,
+                    )
+
+                    memory_transfer_reqs.append(memory_transfer_req)
+
+            execute_model_req.memory_transfer_requests = memory_transfer_reqs
+
2515
+            outputs, request_notif_counter = self.model_executor.execute_model(
ptarasiewiczNV's avatar
ptarasiewiczNV committed
2516
2517
2518
2519
2520
                 execute_model_req=execute_model_req)
-
             # We need to do this here so that last step's sampled_token_ids can
             # be passed to the next iteration for PP.
             if self.scheduler_config.is_multi_step:
2521
@@ -1396,7 +1509,20 @@ class LLMEngine:
ptarasiewiczNV's avatar
ptarasiewiczNV committed
2522
2523
2524
2525
2526
2527
2528
2529
2530
2531
             if len(ctx.output_queue) > 0:
                 self._process_model_outputs(ctx=ctx)
             # No outputs in this case
-            outputs = []
+            execute_model_req = ExecuteModelRequest(
+                seq_group_metadata_list=[],
+                blocks_to_swap_in=[],
+                blocks_to_swap_out=[],
+                blocks_to_copy=[])
+
2532
+            outputs, request_notif_counter = self.model_executor.execute_model(
ptarasiewiczNV's avatar
ptarasiewiczNV committed
2533
2534
2535
2536
2537
2538
2539
2540
2541
2542
+                execute_model_req=execute_model_req)
+            
+        for req_id, notif_count in request_notif_counter.items():
+            self._request_notif_counter[req_id] += notif_count
+            if self._request_notif_counter[req_id] > -1:
+                self._finished_prefills.add(req_id)
+                del self._request_notif_counter[req_id]
 
         # Finish the current step for all the sequence groups.
         if self.scheduler_config.is_multi_step:
2543
@@ -1456,7 +1582,7 @@ class LLMEngine:
ptarasiewiczNV's avatar
ptarasiewiczNV committed
2544
2545
2546
2547
2548
2549
2550
2551
             # queued control plane messages, such as add/remove lora adapters.
             logger.debug("Stopping remote worker execution loop.")
             self.model_executor.stop_remote_worker_execution_loop()
-
+            
         return ctx.request_outputs
 
     def _has_remaining_steps(
GuanLuo's avatar
GuanLuo committed
2552
diff --git a/vllm/engine/multiprocessing/__init__.py b/vllm/engine/multiprocessing/__init__.py
ptarasiewiczNV's avatar
ptarasiewiczNV committed
2553
index 3cf1850e..6b90ece7 100644
GuanLuo's avatar
GuanLuo committed
2554
2555
--- a/vllm/engine/multiprocessing/__init__.py
+++ b/vllm/engine/multiprocessing/__init__.py
ptarasiewiczNV's avatar
ptarasiewiczNV committed
2556
2557
2558
2559
2560
2561
2562
2563
2564
2565
@@ -14,13 +14,17 @@ from vllm.outputs import RequestOutput
 from vllm.prompt_adapter.request import PromptAdapterRequest
 from vllm.sampling_params import SamplingParams
 from vllm.utils import deprecate_kwargs
-
+from vllm.remote_prefill import RemotePrefillParams
+from vllm.distributed.device_communicators.nixl import NixlMetadata
 VLLM_RPC_SUCCESS_STR = "SUCCESS"
 
 IPC_INPUT_EXT = "_input_socket"
GuanLuo's avatar
GuanLuo committed
2566
2567
2568
 IPC_OUTPUT_EXT = "_output_socket"
 IPC_HEALTH_EXT = "_health_socket"
 IPC_DATA_EXT = "_data_socket"
ptarasiewiczNV's avatar
ptarasiewiczNV committed
2569
2570
+IPC_REMOTE_PREFILL_REQUEST_EXT = "_remote_prefill_request_socket"
+IPC_REMOTE_NIXL_METADATA_EXT = "_remote_nixl_metadata_socket"
GuanLuo's avatar
GuanLuo committed
2571
2572
2573
2574
+IPC_METRICS_EXT = "_metrics_socket"
 
 
 class MQEngineDeadError(RuntimeError):
ptarasiewiczNV's avatar
ptarasiewiczNV committed
2575
2576
2577
2578
2579
2580
2581
2582
2583
2584
2585
2586
2587
2588
2589
2590
2591
2592
2593
2594
2595
2596
2597
2598
2599
2600
2601
2602
2603
2604
2605
2606
2607
2608
2609
@@ -36,6 +40,7 @@ class RPCProcessRequest:
     trace_headers: Optional[Mapping[str, str]] = None
     prompt_adapter_request: Optional[PromptAdapterRequest] = None
     priority: int = 0
+    remote_prefill_params: Optional[RemotePrefillParams] = None
 
     @overload
     def __init__(
@@ -78,6 +83,7 @@ class RPCProcessRequest:
             trace_headers: Optional[Mapping[str, str]] = None,
             prompt_adapter_request: Optional[PromptAdapterRequest] = None,
             priority: int = 0,
+            remote_prefill_params: Optional[RemotePrefillParams] = None,
             *,
             inputs: Optional[PromptType] = None,  # DEPRECATED
     ) -> None:
@@ -95,7 +101,7 @@ class RPCProcessRequest:
         self.trace_headers = trace_headers
         self.prompt_adapter_request = prompt_adapter_request
         self.priority = priority
-
+        self.remote_prefill_params = remote_prefill_params
 
 @dataclass
 class RPCError:
@@ -116,7 +122,7 @@ class RPCStartupRequest(Enum):
 @dataclass
 class RPCStartupResponse:
     tracing_enabled: bool
-
+    nixl_metadata: Optional[bytes] = None
 
 class RPCUProfileRequest(Enum):
     START_PROFILE = 1
@@ -157,3 +163,10 @@ def ENGINE_DEAD_ERROR(
GuanLuo's avatar
GuanLuo committed
2610
2611
2612
2613
2614
2615
2616
2617
2618
2619
2620
     return MQEngineDeadError(
         "Engine loop is not running. Inspect the stacktrace to "
         f"find the original error: {repr(error)}.")
+
+@dataclass
+class KvMetrics:
+    request_active_slots: int
+    request_total_slots: int
+    kv_active_blocks: int
+    kv_total_blocks: int
diff --git a/vllm/engine/multiprocessing/client.py b/vllm/engine/multiprocessing/client.py
2621
index 85b5f31e..d33d546a 100644
GuanLuo's avatar
GuanLuo committed
2622
2623
--- a/vllm/engine/multiprocessing/client.py
+++ b/vllm/engine/multiprocessing/client.py
ptarasiewiczNV's avatar
ptarasiewiczNV committed
2624
2625
2626
2627
2628
2629
2630
2631
2632
@@ -8,6 +8,7 @@ from typing import (Any, AsyncGenerator, Dict, Iterator, List, Mapping,
                     Optional, Union, cast, overload)
 
 import cloudpickle
+import msgspec
 import psutil
 import zmq
 import zmq.asyncio
@@ -25,14 +26,16 @@ from vllm.engine.async_llm_engine import (
GuanLuo's avatar
GuanLuo committed
2633
2634
2635
2636
     build_guided_decoding_logits_processor_async)
 from vllm.engine.multiprocessing import (ENGINE_DEAD_ERROR, IPC_DATA_EXT,
                                          IPC_HEALTH_EXT, IPC_INPUT_EXT,
-                                         IPC_OUTPUT_EXT, RPC_REQUEST_T,
ptarasiewiczNV's avatar
ptarasiewiczNV committed
2637
2638
-                                         VLLM_RPC_SUCCESS_STR, RPCAbortRequest,
+                                         IPC_OUTPUT_EXT, IPC_REMOTE_PREFILL_REQUEST_EXT,
GuanLuo's avatar
GuanLuo committed
2639
+                                         RPC_REQUEST_T,
ptarasiewiczNV's avatar
ptarasiewiczNV committed
2640
2641
+                                         VLLM_RPC_SUCCESS_STR, IPC_REMOTE_NIXL_METADATA_EXT, RPCAbortRequest,
+                                         IPC_METRICS_EXT,
GuanLuo's avatar
GuanLuo committed
2642
2643
2644
2645
2646
2647
2648
2649
2650
2651
                                          RPCAdapterLoadedResponse, RPCError,
                                          RPCLoadAdapterRequest,
                                          RPCProcessRequest,
                                          RPCResetPrefixCacheRequest,
                                          RPCStartupRequest, RPCStartupResponse,
-                                         RPCUProfileRequest)
+                                         RPCUProfileRequest, KvMetrics)
 from vllm.engine.protocol import EngineClient
 # yapf: enable
 from vllm.envs import VLLM_RPC_TIMEOUT
ptarasiewiczNV's avatar
ptarasiewiczNV committed
2652
2653
2654
2655
2656
2657
2658
2659
2660
2661
2662
2663
2664
2665
2666
2667
2668
2669
@@ -46,6 +49,8 @@ from vllm.prompt_adapter.request import PromptAdapterRequest
 from vllm.sampling_params import SamplingParams
 from vllm.transformers_utils.tokenizer_group import init_tokenizer_from_configs
 from vllm.utils import deprecate_kwargs
+from vllm.remote_prefill import RemotePrefillParams, RemotePrefillRequest, RemotePrefillRequestCallback
+from vllm.distributed.device_communicators.nixl import NixlMetadata
 
 logger = init_logger(__name__)
 
@@ -91,6 +96,7 @@ class MQLLMEngineClient(EngineClient):
         self._errored_with: Optional[BaseException] = None
 
         # Get the configs.
+        self.vllm_config = engine_config
         self.model_config = engine_config.model_config
         self.decoding_config = engine_config.decoding_config
 
@@ -115,6 +121,10 @@ class MQLLMEngineClient(EngineClient):
GuanLuo's avatar
GuanLuo committed
2670
2671
2672
2673
2674
2675
2676
2677
2678
2679
         self.heartbeat_socket: Socket = self.context.socket(zmq.constants.PULL)
         self.heartbeat_socket.connect(f"{ipc_path}{IPC_HEALTH_EXT}")
 
+        # Metrics.
+        self.metrics_socket: Socket = self.context.socket(zmq.constants.PULL)
+        self.metrics_socket.connect(f"{ipc_path}{IPC_METRICS_EXT}")
+
         # IPC path for the data socket.
         self.data_ipc_path = f"{ipc_path}{IPC_DATA_EXT}"
 
ptarasiewiczNV's avatar
ptarasiewiczNV committed
2680
@@ -129,8 +139,27 @@ class MQLLMEngineClient(EngineClient):
GuanLuo's avatar
GuanLuo committed
2681
2682
2683
2684
2685
2686
2687
2688
2689
2690
2691
         # Loop to check health of the LLMEngine periodically.
         # Started after the MQLLMEngine is ready.
         self.health_loop: Optional[asyncio.Task] = None
+
+        # Loop to check metrics of the LLMEngine periodically.
+        # Started after the MQLLMEngine is ready.
+        self.metrics_loop: Optional[asyncio.Task] = None
+        self.metrics_publisher = None
+
         self._engine_process = psutil.Process(engine_pid)
 
ptarasiewiczNV's avatar
ptarasiewiczNV committed
2692
2693
2694
2695
2696
2697
2698
2699
2700
2701
2702
+        self.nixl_metadata: Optional[NixlMetadata] = None
+        self.remote_prefill_request_socket: Socket = self.context.socket(zmq.constants.PULL)
+        self.remote_nixl_metadata_socket: Socket = self.context.socket(zmq.constants.PUSH)
+        self.remote_prefill_requests_callback: Dict[str, RemotePrefillRequestCallback] = {}
+        if self.using_nixl_connector:
+            self.remote_prefill_request_socket.connect(f"{ipc_path}{IPC_REMOTE_PREFILL_REQUEST_EXT}")
+            self.remote_nixl_metadata_socket.connect(f"{ipc_path}{IPC_REMOTE_NIXL_METADATA_EXT}")
+
+    
+    @property
+    def using_nixl_connector(self) -> bool:
2703
+        return self.vllm_config.kv_transfer_config is not None and self.vllm_config.kv_transfer_config.kv_connector == "DynemoNixlConnector"
ptarasiewiczNV's avatar
ptarasiewiczNV committed
2704
+
GuanLuo's avatar
GuanLuo committed
2705
     @staticmethod
ptarasiewiczNV's avatar
ptarasiewiczNV committed
2706
2707
2708
     def is_unsupported_config(engine_args: AsyncEngineArgs):
         # Pipeline parallel not yet supported
@@ -180,6 +209,56 @@ class MQLLMEngineClient(EngineClient):
GuanLuo's avatar
GuanLuo committed
2709
2710
2711
         except Exception as e:
             self._set_errored(e)
 
ptarasiewiczNV's avatar
ptarasiewiczNV committed
2712
2713
2714
2715
2716
2717
2718
2719
2720
2721
+    async def run_remote_prefill_request_handler_loop(self):
+        try:
+            while True:
+                if await self.remote_prefill_request_socket.poll(timeout=VLLM_RPC_TIMEOUT):
+                    frames = await self.remote_prefill_request_socket.recv(copy=False)
+                    remote_prefill_request = msgspec.msgpack.decode(frames.buffer, type=RemotePrefillRequest)
+                    await self.remote_prefill_requests_callback[remote_prefill_request.request_id](remote_prefill_request)
+        except asyncio.CancelledError:
+            logger.debug("Shutting down MQLLMEngineClient remote prefill request handler loop.")
+            
GuanLuo's avatar
GuanLuo committed
2722
2723
2724
2725
2726
2727
2728
2729
2730
2731
2732
2733
2734
2735
2736
2737
2738
2739
2740
2741
2742
2743
2744
2745
2746
2747
2748
+    async def run_metrics_loop(self, timeout: int):
+        """Background loop that continually checks to ensure the engine process
+        is still alive.
+        """
+        try:
+            while True:
+                # Check if the engine process is running:
+                if not self._engine_process.is_running() or (
+                        self._engine_process.status() == psutil.STATUS_ZOMBIE):
+                    # NB: is_running() returns True for zombies
+                    self._set_errored(
+                        RuntimeError(
+                            f"Engine process (pid {self._engine_process.pid}) "
+                            "died."))
+                    break
+
+                if await self.metrics_socket.poll(timeout=timeout):
+                    # Metrics received- check the message
+                    message: Frame = await self.metrics_socket.recv(copy=False)
+                    kv_metrics = pickle.loads(message.buffer)
+                    if self.metrics_publisher is not None:
+                        if isinstance(kv_metrics, KvMetrics):
+                            self.metrics_publisher.publish(kv_metrics.request_active_slots,
+                                                        kv_metrics.request_total_slots,
+                                                        kv_metrics.kv_active_blocks,
+                                                        kv_metrics.kv_total_blocks)
+
2749
+                logger.debug("Metircs successful.")
GuanLuo's avatar
GuanLuo committed
2750
2751
2752
2753
2754
2755
2756
2757
2758
2759
2760
2761
2762
2763
2764
+
+        except asyncio.CancelledError:
+            logger.debug("Shutting down MQLLMEngineClient check metrics loop.")
+
+        except psutil.NoSuchProcess:
+            self._set_errored(
+                RuntimeError(
+                    f"Engine process (pid {self._engine_process.pid}) died."))
+
+        except Exception as e:
+            self._set_errored(e)
+
     async def run_output_handler_loop(self):
         """Get RequestOutputs from Engine and stream to Request Queues"""
 
ptarasiewiczNV's avatar
ptarasiewiczNV committed
2765
2766
2767
2768
2769
2770
2771
2772
2773
2774
2775
@@ -278,12 +357,26 @@ class MQLLMEngineClient(EngineClient):
             # Wait until server is ready.
             response = await self._wait_for_server_rpc(socket)
 
+            if response.nixl_metadata is not None:
+                assert self.using_nixl_connector
+                self.nixl_metadata = msgspec.msgpack.decode(response.nixl_metadata, type=NixlMetadata)
+
             self.tracing_flag = response.tracing_enabled
 
             # Start health_loop.
GuanLuo's avatar
GuanLuo committed
2776
2777
2778
2779
             if self.health_loop is None:
                 self.health_loop = asyncio.create_task(
                     self.run_heartbeat_loop(timeout=VLLM_RPC_TIMEOUT))
+                
ptarasiewiczNV's avatar
ptarasiewiczNV committed
2780
2781
2782
2783
+            if self.using_nixl_connector:
+                self.remote_prefill_loop = asyncio.create_task(
+                    self.run_remote_prefill_request_handler_loop())
+                    
GuanLuo's avatar
GuanLuo committed
2784
2785
2786
2787
2788
2789
2790
2791
+            # Start metrics_loop.
+            if self.metrics_loop is None:
+                self.metrics_loop = asyncio.create_task(
+                    self.run_metrics_loop(timeout=VLLM_RPC_TIMEOUT))
+
 
     def close(self):
         """Destroy the ZeroMQ Context."""
ptarasiewiczNV's avatar
ptarasiewiczNV committed
2792
@@ -293,6 +386,8 @@ class MQLLMEngineClient(EngineClient):
GuanLuo's avatar
GuanLuo committed
2793
2794
2795
2796
2797
2798
2799
2800
         # Cancel background tasks.
         if self.health_loop is not None:
             self.health_loop.cancel()
+        if self.metrics_loop is not None:
+            self.metrics_loop.cancel()
         if self.output_loop is not None:
             self.output_loop.cancel()
 
ptarasiewiczNV's avatar
ptarasiewiczNV committed
2801
2802
2803
2804
2805
2806
2807
2808
2809
2810
2811
2812
2813
2814
2815
2816
2817
2818
2819
2820
2821
2822
2823
2824
2825
2826
2827
2828
2829
2830
2831
2832
2833
2834
2835
2836
2837
2838
2839
2840
2841
2842
2843
2844
2845
2846
2847
2848
2849
2850
2851
2852
2853
2854
2855
2856
2857
2858
2859
2860
2861
2862
2863
2864
@@ -415,6 +510,9 @@ class MQLLMEngineClient(EngineClient):
         """
         if self._errored_with is not None:
             raise self._errored_with
+        
+    async def add_remote_nixl_metadata(self, nixl_metadata: NixlMetadata):
+        await self.remote_nixl_metadata_socket.send(msgspec.msgpack.encode(nixl_metadata), copy=False)
 
     @property
     def is_running(self) -> bool:
@@ -473,6 +571,7 @@ class MQLLMEngineClient(EngineClient):
         trace_headers: Optional[Mapping[str, str]] = None,
         prompt_adapter_request: Optional[PromptAdapterRequest] = None,
         priority: int = 0,
+        remote_prefill_params: Optional[RemotePrefillParams] = None,
         *,
         inputs: Optional[PromptType] = None  # DEPRECATED
     ) -> AsyncGenerator[RequestOutput, None]:
@@ -502,7 +601,8 @@ class MQLLMEngineClient(EngineClient):
 
         return self._process_request(prompt, sampling_params, request_id,
                                      lora_request, trace_headers,
-                                     prompt_adapter_request, priority)
+                                     prompt_adapter_request, priority,
+                                     remote_prefill_params)
 
     @overload
     def encode(
@@ -586,6 +686,7 @@ class MQLLMEngineClient(EngineClient):
         trace_headers: Optional[Mapping[str, str]] = None,
         prompt_adapter_request: Optional[PromptAdapterRequest] = None,
         priority: int = 0,
+        remote_prefill_params: Optional[RemotePrefillParams] = None,
     ) -> Union[AsyncGenerator[RequestOutput, None], AsyncGenerator[
             PoolingRequestOutput, None]]:
         """Send an RPCGenerateRequest to the RPCServer and stream responses."""
@@ -630,6 +731,12 @@ class MQLLMEngineClient(EngineClient):
             else:
                 lp_bytes = None
 
+            if remote_prefill_params is not None:
+                self.remote_prefill_requests_callback[request_id] = remote_prefill_params.remote_prefill_request_callback
+                remote_prefill_params.remote_prefill_request_callback = None
+            else:
+                remote_prefill_request_callback = None
+
             request_bytes = pickle.dumps(
                 RPCProcessRequest(
                     prompt=prompt,
@@ -639,11 +746,11 @@ class MQLLMEngineClient(EngineClient):
                     trace_headers=trace_headers,
                     prompt_adapter_request=prompt_adapter_request,
                     priority=priority,
+                    remote_prefill_params=remote_prefill_params,
                 ))
 
             # 3) Send the RPCGenerateRequest to the MQLLMEngine.
-            parts = (request_bytes,
-                     lp_bytes) if lp_bytes else (request_bytes, )
+            parts = (request_bytes, lp_bytes) if lp_bytes else (request_bytes,)
             await self.input_socket.send_multipart(parts, copy=False)
 
             # 4) Stream the RequestOutputs from the output queue. Note
@@ -705,3 +812,6 @@ class MQLLMEngineClient(EngineClient):
GuanLuo's avatar
GuanLuo committed
2865
2866
2867
2868
2869
2870
2871
         # Raise on error, otherwise happily return None
         if isinstance(request_output, BaseException):
             raise request_output
+
+    def set_metrics_publisher(self, metrics_publisher):
+        self.metrics_publisher = metrics_publisher
diff --git a/vllm/engine/multiprocessing/engine.py b/vllm/engine/multiprocessing/engine.py
ptarasiewiczNV's avatar
ptarasiewiczNV committed
2872
index a0dd7958..dbd9d58d 100644
GuanLuo's avatar
GuanLuo committed
2873
2874
--- a/vllm/engine/multiprocessing/engine.py
+++ b/vllm/engine/multiprocessing/engine.py
ptarasiewiczNV's avatar
ptarasiewiczNV committed
2875
2876
2877
2878
2879
2880
2881
2882
2883
2884
2885
2886
2887
2888
2889
@@ -3,35 +3,73 @@
 import pickle
 import signal
 from contextlib import contextmanager
-from typing import Iterator, List, Optional, Union
+from typing import Iterator, List, Optional, Union, Dict
 
 import cloudpickle
+import time
 import zmq
-
+import msgspec
 from vllm import AsyncEngineArgs, SamplingParams
 from vllm.engine.llm_engine import LLMEngine
 # yapf conflicts with isort for this block
GuanLuo's avatar
GuanLuo committed
2890
2891
2892
2893
 # yapf: disable
 from vllm.engine.multiprocessing import (ENGINE_DEAD_ERROR, IPC_DATA_EXT,
                                          IPC_HEALTH_EXT, IPC_INPUT_EXT,
-                                         IPC_OUTPUT_EXT, REQUEST_OUTPUTS_T,
ptarasiewiczNV's avatar
ptarasiewiczNV committed
2894
-                                         VLLM_RPC_SUCCESS_STR, RPCAbortRequest,
GuanLuo's avatar
GuanLuo committed
2895
+                                         REQUEST_OUTPUTS_T,
ptarasiewiczNV's avatar
ptarasiewiczNV committed
2896
2897
2898
+                                         VLLM_RPC_SUCCESS_STR, IPC_REMOTE_PREFILL_REQUEST_EXT,
+                                         RPCAbortRequest,
+                                         IPC_OUTPUT_EXT, IPC_METRICS_EXT,
GuanLuo's avatar
GuanLuo committed
2899
2900
2901
2902
2903
2904
                                          RPCAdapterLoadedResponse, RPCError,
                                          RPCLoadAdapterRequest,
                                          RPCProcessRequest,
                                          RPCResetPrefixCacheRequest,
                                          RPCStartupRequest, RPCStartupResponse,
-                                         RPCUProfileRequest)
ptarasiewiczNV's avatar
ptarasiewiczNV committed
2905
2906
+                                         RPCUProfileRequest, IPC_REMOTE_NIXL_METADATA_EXT,
+                                         KvMetrics)
GuanLuo's avatar
GuanLuo committed
2907
2908
2909
2910
 # yapf: enable
 from vllm.logger import init_logger
 from vllm.outputs import RequestOutput
 from vllm.usage.usage_lib import UsageContext
ptarasiewiczNV's avatar
ptarasiewiczNV committed
2911
2912
2913
+from vllm.remote_prefill import RemotePrefillRequest
+from vllm.distributed.device_communicators.nixl import NixlMetadata
+
GuanLuo's avatar
GuanLuo committed
2914
2915
2916
2917
2918
2919
2920
2921
2922
2923
2924
2925
2926
2927
2928
2929
2930
2931
2932
2933
2934
2935
2936
2937
2938
2939
2940
2941
2942
2943
2944
2945
2946
2947
2948
2949
2950
2951
2952
2953
+from vllm.engine.metrics_types import StatLoggerBase, Stats, SupportsMetricsInfo
+from dataclasses import dataclass, field
 
 logger = init_logger(__name__)
 
 POLLING_TIMEOUT_MS = 10000
 HEALTHY_RESPONSE = (pickle.dumps(VLLM_RPC_SUCCESS_STR), )
 
+class KvStatLogger(StatLoggerBase):
+    def __init__(
+        self,
+        max_num_seqs: int,
+        num_total_gpu_blocks: int,
+        metrics_socket
+    ):
+        # Must query initialized scheduler for max infos
+        self.request_total_slots = max_num_seqs
+        self.kv_total_blocks = num_total_gpu_blocks
+        self.metrics_socket = metrics_socket
+
+        # KV metrics
+        self._send_kv_metrics(0, 0)
+
+    def log(self, stats: Stats) -> None:
+        self._send_kv_metrics(
+            stats.num_running_sys,
+            int(stats.gpu_cache_usage_sys * self.kv_total_blocks)
+        )
+
+    def info(self, type: str, obj: SupportsMetricsInfo) -> None:
+        pass
+
+    def _send_kv_metrics(self, active_slots, active_kv_blocks):
+        if not self.metrics_socket.closed:
+            metrics_bytes = pickle.dumps(KvMetrics(active_slots, self.request_total_slots, active_kv_blocks, self.kv_total_blocks))
+            self.metrics_socket.send_multipart((metrics_bytes, ), copy=False)
+
 
 class MQLLMEngine:
     """A multiprocessing wrapper for :class:`LLMEngine`.
ptarasiewiczNV's avatar
ptarasiewiczNV committed
2954
@@ -94,12 +132,31 @@ class MQLLMEngine:
GuanLuo's avatar
GuanLuo committed
2955
2956
2957
2958
2959
2960
2961
2962
2963
2964
2965
2966
2967
         self.heartbeat_socket = self.ctx.socket(zmq.constants.PUSH)
         self.heartbeat_socket.bind(f"{ipc_path}{IPC_HEALTH_EXT}")
 
+        # Send metrics back to client.
+        self.metrics_socket = self.ctx.socket(zmq.constants.PUSH)
+        self.metrics_socket.bind(f"{ipc_path}{IPC_METRICS_EXT}")
+
         # IPC path for the data socket.
         self.data_ipc_path = f"{ipc_path}{IPC_DATA_EXT}"
 
         # Error state.
         self._errored_with: Optional[BaseException] = None
 
ptarasiewiczNV's avatar
ptarasiewiczNV committed
2968
2969
2970
2971
2972
2973
2974
+        self.remote_prefill_request_socket = self.ctx.socket(zmq.constants.PUSH)
+        self.remote_nixl_metadata_socket = self.ctx.socket(zmq.constants.PULL)
+        if self.engine.is_nixl_initialized:
+            self.remote_prefill_request_socket.bind(f"{ipc_path}{IPC_REMOTE_PREFILL_REQUEST_EXT}")
+            self.remote_nixl_metadata_socket.bind(f"{ipc_path}{IPC_REMOTE_NIXL_METADATA_EXT}")
+
+
GuanLuo's avatar
GuanLuo committed
2975
2976
2977
2978
2979
2980
2981
2982
2983
2984
2985
+        # Attach logger for continuous metrics publishing
+        self.stat_logger = KvStatLogger(
+            self.engine.scheduler_config.max_num_seqs,
+            self.engine.cache_config.num_gpu_blocks,
+            self.metrics_socket
+        )
+        self.engine.add_logger("kv_metrics", self.stat_logger)
+
     @property
     def dead_error(self) -> BaseException:
         if self._errored_with is not None:
ptarasiewiczNV's avatar
ptarasiewiczNV committed
2986
2987
2988
2989
2990
2991
2992
2993
2994
2995
2996
2997
2998
2999
3000
3001
3002
3003
3004
3005
3006
3007
3008
3009
3010
3011
3012
3013
3014
3015
3016
3017
3018
3019
3020
3021
3022
3023
3024
3025
3026
3027
3028
3029
3030
3031
3032
3033
3034
3035
3036
3037
3038
3039
3040
3041
3042
3043
3044
3045
3046
3047
3048
3049
3050
3051
3052
3053
3054
3055
3056
3057
3058
3059
3060
3061
3062
3063
3064
3065
3066
3067
3068
3069
3070
3071
3072
3073
3074
3075
3076
3077
3078
@@ -171,8 +228,17 @@ class MQLLMEngine:
                 # Handle the query from the Client.
                 if request == RPCStartupRequest.IS_SERVER_READY:
                     tracing_enabled = self.engine.is_tracing_enabled()
-                    response = RPCStartupResponse(
-                        tracing_enabled=tracing_enabled)
+            
+                    # Send nixl metadata to the client
+                    if self.engine.is_nixl_initialized:
+                        nixl_metadata = self.engine.get_nixl_metadata()
+                        encoded_nixl_metadata = msgspec.msgpack.encode(nixl_metadata)
+                        response = RPCStartupResponse(
+                            tracing_enabled=tracing_enabled,
+                            nixl_metadata=encoded_nixl_metadata)
+                    else:
+                        response = RPCStartupResponse(
+                            tracing_enabled=tracing_enabled)
 
             except Exception as e:
                 response = e
@@ -185,6 +251,7 @@ class MQLLMEngine:
 
         while True:
             if not self.engine.has_unfinished_requests():
+                logger.debug("No unfinished requests")
                 # Poll until there is work to do.
                 while self.input_socket.poll(timeout=POLLING_TIMEOUT_MS) == 0:
                     # When there's no work, check on engine health and send
@@ -220,6 +287,13 @@ class MQLLMEngine:
     def handle_new_input(self):
         """Handle new input from the socket"""
         try:
+            if self.engine.is_nixl_initialized:
+                while self.remote_nixl_metadata_socket.poll(timeout=0) != 0:
+                    frames = self.remote_nixl_metadata_socket.recv(copy=False)
+                    nixl_metadata = msgspec.msgpack.decode(frames.buffer, type=NixlMetadata)
+                    logger.debug("Adding remote nixl metadata for engine: %s", nixl_metadata.engine_id)
+                    self.engine.add_remote_nixl_metadata(nixl_metadata)
+
             while self.input_socket.poll(timeout=0) != 0:
                 frames = self.input_socket.recv_multipart(copy=False)
                 request = pickle.loads(frames[0].buffer)
@@ -262,6 +336,11 @@ class MQLLMEngine:
             self._send_outputs(rpc_err)
 
         try:
+            if request.remote_prefill_params is not None and request.remote_prefill_params.is_remote_prefill:
+                def remote_prefill_request_callback(request: RemotePrefillRequest):
+                    logger.debug("Sending remote prefill request: %s", request.request_id)
+                    self.remote_prefill_request_socket.send(msgspec.msgpack.encode(request), copy=False)
+                request.remote_prefill_params.remote_prefill_request_callback = remote_prefill_request_callback
             self.engine.add_request(
                 request_id=request_id,
                 prompt=request.prompt,
@@ -269,7 +348,9 @@ class MQLLMEngine:
                 lora_request=request.lora_request,
                 trace_headers=request.trace_headers,
                 prompt_adapter_request=request.prompt_adapter_request,
-                priority=request.priority)
+                priority=request.priority,
+                remote_prefill_params=request.remote_prefill_params,
+            )
 
             if self.log_requests:
                 logger.info("Added request %s.", request.request_id)
diff --git a/vllm/entrypoints/openai/serving_chat.py b/vllm/entrypoints/openai/serving_chat.py
index 107220d5..c716f75f 100644
--- a/vllm/entrypoints/openai/serving_chat.py
+++ b/vllm/entrypoints/openai/serving_chat.py
@@ -34,6 +34,7 @@ from vllm.sampling_params import BeamSearchParams, SamplingParams
 from vllm.sequence import Logprob
 from vllm.transformers_utils.tokenizer import AnyTokenizer, MistralTokenizer
 from vllm.transformers_utils.tokenizers import maybe_serialize_tool_calls
+from vllm.remote_prefill import RemotePrefillParams
 
 logger = init_logger(__name__)
 
@@ -112,6 +113,7 @@ class OpenAIServingChat(OpenAIServing):
         self,
         request: ChatCompletionRequest,
         raw_request: Optional[Request] = None,
+        remote_prefill_params: Optional[RemotePrefillParams] = None,
     ) -> Union[AsyncGenerator[str, None], ChatCompletionResponse,
                ErrorResponse]:
         """
@@ -243,6 +245,7 @@ class OpenAIServingChat(OpenAIServing):
                         trace_headers=trace_headers,
                         prompt_adapter_request=prompt_adapter_request,
                         priority=request.priority,
+                        remote_prefill_params=remote_prefill_params,
                     )
 
                 generators.append(generator)
3079
diff --git a/vllm/envs.py b/vllm/envs.py
GuanLuo's avatar
GuanLuo committed
3080
index 745b068b..0ae63d9b 100644
3081
3082
--- a/vllm/envs.py
+++ b/vllm/envs.py
GuanLuo's avatar
GuanLuo committed
3083
@@ -87,6 +87,10 @@ if TYPE_CHECKING:
3084
3085
3086
3087
     VLLM_ENABLE_MOE_ALIGN_BLOCK_SIZE_TRITON: bool = False
     VLLM_RAY_PER_WORKER_GPUS: float = 1.0
     VLLM_RAY_BUNDLE_INDICES: str = ""
+    VLLM_KV_CAPI_PATH: Optional[str] = None
GuanLuo's avatar
GuanLuo committed
3088
3089
3090
+    VLLM_KV_NAMESPACE: Optional[str] = None
+    VLLM_KV_COMPONENT: Optional[str] = None
+    VLLM_WORKER_ID: Optional[int] = None
3091
3092
3093
 
 
 def get_default_cache_root():
GuanLuo's avatar
GuanLuo committed
3094
@@ -572,6 +576,21 @@ environment_variables: Dict[str, Callable[[], Any]] = {
3095
3096
3097
3098
3099
3100
3101
3102
     # models the alignment is already naturally aligned to 256 bytes.
     "VLLM_CUDA_MEM_ALIGN_KV_CACHE":
     lambda: bool(int(os.getenv("VLLM_CUDA_MEM_ALIGN_KV_CACHE", "1"))),
+
+    # Path to the C API Library
+    "VLLM_KV_CAPI_PATH":
+    lambda: os.environ.get("VLLM_KV_CAPI_PATH", None),
+
GuanLuo's avatar
GuanLuo committed
3103
3104
3105
3106
3107
3108
+    # Identifiers to publish KV related information
+    "VLLM_KV_NAMESPACE":
+    lambda: os.environ.get("VLLM_KV_NAMESPACE", None),
+    "VLLM_KV_COMPONENT":
+    lambda: os.environ.get("VLLM_KV_COMPONENT", None),
+
3109
3110
+    # Worker ID used for identifying workers in distributed settings
+    "VLLM_WORKER_ID":
GuanLuo's avatar
GuanLuo committed
3111
3112
+    lambda: int(os.getenv("VLLM_WORKER_ID", "0"))
+    if "VLLM_WORKER_ID" in os.environ else None,
3113
3114
3115
 }
 
 # end-env-vars-definition
3116
3117
3118
3119
3120
3121
3122
3123
3124
3125
3126
3127
3128
diff --git a/vllm/model_executor/models/deepseek_v2.py b/vllm/model_executor/models/deepseek_v2.py
index 773f5abe..3eefd266 100644
--- a/vllm/model_executor/models/deepseek_v2.py
+++ b/vllm/model_executor/models/deepseek_v2.py
@@ -585,6 +585,8 @@ class DeepseekV2Model(nn.Module):
         cache_config = vllm_config.cache_config
         quant_config = vllm_config.quant_config
 
+        self.config = config
+
         self.padding_idx = config.pad_token_id
         self.vocab_size = config.vocab_size
 
ptarasiewiczNV's avatar
ptarasiewiczNV committed
3129
3130
3131
3132
3133
3134
3135
3136
3137
3138
3139
3140
3141
3142
3143
3144
3145
3146
3147
3148
3149
3150
3151
3152
3153
diff --git a/vllm/outputs.py b/vllm/outputs.py
index 786380c3..56a7cf89 100644
--- a/vllm/outputs.py
+++ b/vllm/outputs.py
@@ -6,16 +6,16 @@ from typing import Dict, Generic, List, MutableSequence, Optional
 from typing import Sequence as GenericSequence
 from typing import Union
 
+import msgspec
 import torch
 from typing_extensions import TypeVar, deprecated
 
 from vllm.lora.request import LoRARequest
 from vllm.multimodal.inputs import MultiModalPlaceholderDict
-from vllm.sampling_params import RequestOutputKind
+from vllm.sampling_params import RequestOutputKind, SamplingParams
 from vllm.sequence import (PromptLogprobs, RequestMetrics, SampleLogprobs,
                            SequenceGroup, SequenceGroupBase, SequenceStatus)
 
-
 @dataclass
 class CompletionOutput:
     """The output data of one completion output of a request.
diff --git a/vllm/remote_prefill.py b/vllm/remote_prefill.py
new file mode 100644
3154
index 00000000..03f02006
ptarasiewiczNV's avatar
ptarasiewiczNV committed
3155
3156
--- /dev/null
+++ b/vllm/remote_prefill.py
3157
@@ -0,0 +1,53 @@
ptarasiewiczNV's avatar
ptarasiewiczNV committed
3158
3159
3160
3161
3162
3163
3164
3165
3166
3167
3168
3169
3170
3171
3172
3173
3174
3175
3176
3177
3178
3179
3180
3181
3182
3183
3184
3185
3186
3187
3188
3189
3190
3191
3192
3193
3194
3195
3196
3197
3198
3199
3200
3201
3202
3203
3204
3205
3206
3207
3208
3209
3210
3211
3212
3213
3214
3215
3216
3217
3218
3219
3220
3221
3222
3223
3224
3225
3226
3227
3228
3229
3230
3231
3232
3233
3234
3235
3236
3237
3238
3239
3240
3241
3242
3243
3244
3245
3246
3247
3248
3249
3250
3251
3252
3253
3254
3255
3256
3257
3258
3259
3260
3261
3262
3263
3264
3265
3266
3267
3268
3269
3270
3271
3272
3273
3274
3275
3276
3277
3278
3279
3280
3281
3282
3283
3284
3285
3286
3287
3288
3289
3290
3291
3292
3293
3294
3295
3296
3297
3298
3299
3300
3301
3302
3303
3304
3305
3306
3307
3308
3309
3310
3311
3312
3313
3314
3315
3316
3317
3318
3319
3320
3321
3322
3323
3324
3325
3326
3327
3328
3329
3330
3331
3332
3333
3334
3335
3336
3337
+from dataclasses import dataclass
+from typing import Callable, Optional, List, Coroutine
+
+import msgspec
+
+from vllm.sampling_params import SamplingParams
+
+
+class RemotePrefillRequest(
+        msgspec.Struct,
+        omit_defaults=True,  # type: ignore[call-arg]
+        # required for @cached_property.
+        dict=True):
+    """The request data of one remote prefill output of a request.
+
+    Args:
+        request_id: The unique ID of the request.
+        prompt: The prompt string of the request.
+    """
+    request_id: str
+    prompt_token_ids: List[int]
+    sampling_params: SamplingParams
+    block_ids: List[int]
+    engine_id: str
+
+
+class MemoryTransferRequest(
+        msgspec.Struct,
+        array_like=True,  # type: ignore[call-arg]
+        omit_defaults=True):  # type: ignore[call-arg]
+    """The request data of one memory transfer output of a request.
+
+    Args:
+        request_id: The unique ID of the request.
+    """
+    request_id: str
+    src_block_ids: List[int]
+    dst_block_ids: List[int]
+    dst_engine_id: str
+    notify_msg: str
+
+
+RemotePrefillRequestCallback = Callable[[RemotePrefillRequest], None]
+
+
+@dataclass
+class RemotePrefillParams:
+    """Remote prefill parameters for text generation."""
+    is_remote_prefill: bool = False
+    is_remote_decode: bool = False
+    decode_block_ids: Optional[List[int]] = None
+    decode_engine_id: Optional[str] = None
+    remote_prefill_request_callback: Optional[RemotePrefillRequestCallback] = None
\ No newline at end of file
diff --git a/vllm/sampling_params.py b/vllm/sampling_params.py
index 97f9e212..1bb97b00 100644
--- a/vllm/sampling_params.py
+++ b/vllm/sampling_params.py
@@ -83,7 +83,7 @@ class RequestOutputKind(Enum):
     DELTA = 1
     # Do not return intermediate RequestOuputs
     FINAL_ONLY = 2
-
+    
 
 class SamplingParams(
         msgspec.Struct,
diff --git a/vllm/sequence.py b/vllm/sequence.py
index 534b9e60..18675d2f 100644
--- a/vllm/sequence.py
+++ b/vllm/sequence.py
@@ -20,6 +20,7 @@ from vllm.multimodal import MultiModalDataDict, MultiModalPlaceholderDict
 from vllm.pooling_params import PoolingParams
 from vllm.prompt_adapter.request import PromptAdapterRequest
 from vllm.sampling_params import RequestOutputKind, SamplingParams
+from vllm.remote_prefill import RemotePrefillParams, MemoryTransferRequest
 
 VLLM_TOKEN_ID_ARRAY_TYPE = "l"
 
@@ -59,13 +60,14 @@ class SequenceStatus(enum.IntEnum):
     """Status of a sequence."""
     WAITING = 0
     RUNNING = 1
-    SWAPPED = 2
-    # Note: anything after SWAPPED (2) will be considered
+    REMOTE_PREFILLING = 2
+    SWAPPED = 3
+    # Note: anything after SWAPPED (3) will be considered
     # as a finished status.
-    FINISHED_STOPPED = 3
-    FINISHED_LENGTH_CAPPED = 4
-    FINISHED_ABORTED = 5
-    FINISHED_IGNORED = 6
+    FINISHED_STOPPED = 4
+    FINISHED_LENGTH_CAPPED = 5
+    FINISHED_ABORTED = 6
+    FINISHED_IGNORED = 7
 
     @staticmethod
     def is_finished(status: "SequenceStatus") -> bool:
@@ -409,6 +411,7 @@ class Sequence:
         eos_token_id: Optional[int] = None,
         lora_request: Optional[LoRARequest] = None,
         prompt_adapter_request: Optional[PromptAdapterRequest] = None,
+        remote_prefill_params: Optional[RemotePrefillParams] = None,
     ) -> None:
         self.seq_id = seq_id
         self.inputs = SingletonInputsAdapter(inputs)
@@ -416,7 +419,7 @@ class Sequence:
         self.eos_token_id = eos_token_id
         self.lora_request = lora_request
         self.prompt_adapter_request = prompt_adapter_request
-
+        self.remote_prefill_params = remote_prefill_params
         self.data = SequenceData.from_seqs(self.prompt_token_ids)
         self.output_logprobs: SampleLogprobs = []
         self.output_text = ""
@@ -639,6 +642,7 @@ class SequenceGroup:
         trace_headers: OpenTelemetry trace headers.
         prompt_adapter_request: Prompt Adapter request.
         priority: User-defined priority of the request.
+        remote_prefill_params: Remote prefill parameters.
     """
 
     def __init__(
@@ -654,6 +658,7 @@ class SequenceGroup:
         trace_headers: Optional[Mapping[str, str]] = None,
         prompt_adapter_request: Optional[PromptAdapterRequest] = None,
         priority: int = 0,
+        remote_prefill_params: Optional[RemotePrefillParams] = None,
     ) -> None:
         self.request_id = request_id
         self.seqs = seqs
@@ -678,7 +683,7 @@ class SequenceGroup:
         self.encoder_seq = encoder_seq
         self.trace_headers = trace_headers
         self.priority = priority
-
+        self.remote_prefill_params = remote_prefill_params
         self.cached_request_output = None
 
     @property
@@ -927,6 +932,9 @@ class SequenceGroupMetadata(
             query tokens for prefill, we don't need sampling.
         token_chunk_size: The number of tokens to be processed (per sequence).
             None if chunking is not required.
+        do_remote_prefill: True if remote prefill is required.
+        do_remote_decode: True if remote decode is required.
+        decode_memory_desc: The memory descriptor for the decoder blocks.
         lora_request: LoRA request.
         computed_block_nums: The block numbers that are already computed,
             used in prefix caching.
@@ -966,6 +974,9 @@ class SequenceGroupMetadata(
     cross_block_table: Optional[List[int]] = None
     prompt_adapter_request: Optional[PromptAdapterRequest] = None
     token_chunk_size: Optional[int] = None
+    do_remote_prefill: bool = False
+    do_remote_decode: bool = False
+    decode_memory_desc: Optional[bytes] = None
 
     ### Stateful fields that are lazily defined. ###
     # The number of speculative tokens adopted in this request.
@@ -1310,6 +1321,8 @@ class ExecuteModelRequest(
     last_sampled_token_ids: Optional[torch.Tensor] = None
     # Async callback
     async_callback: Optional[Callable] = None
+    # The memory transfer requests.
+    memory_transfer_requests: Optional[List[MemoryTransferRequest]] = None
 
     @property
     def is_first_multi_step(self) -> bool:
diff --git a/vllm/worker/model_runner.py b/vllm/worker/model_runner.py
index 12baecde..cbada27f 100644
--- a/vllm/worker/model_runner.py
+++ b/vllm/worker/model_runner.py
@@ -1824,6 +1824,9 @@ class ModelRunner(GPUModelRunnerBase[ModelInputForGPUWithSamplingMetadata]):
 
         if self.vllm_config.kv_transfer_config is None:
             return False
+        
3338
+        if self.vllm_config.kv_transfer_config.kv_connector == "DynemoNixlConnector":
ptarasiewiczNV's avatar
ptarasiewiczNV committed
3339
3340
3341
3342
3343
3344
3345
3346
3347
+            return False
 
         prefill_meta = model_input.attn_metadata.prefill_metadata
 
@@ -1849,6 +1852,9 @@ class ModelRunner(GPUModelRunnerBase[ModelInputForGPUWithSamplingMetadata]):
 
         if self.vllm_config.kv_transfer_config is None:
             return False
+        
3348
+        if self.vllm_config.kv_transfer_config.kv_connector == "DynemoNixlConnector":
ptarasiewiczNV's avatar
ptarasiewiczNV committed
3349
3350
3351
3352
3353
+            return False
 
         prefill_meta = model_input.attn_metadata.prefill_metadata
 
diff --git a/vllm/worker/worker.py b/vllm/worker/worker.py
3354
index 582aa460..ffb7b403 100644
ptarasiewiczNV's avatar
ptarasiewiczNV committed
3355
3356
3357
3358
3359
3360
3361
3362
3363
3364
3365
3366
3367
3368
3369
--- a/vllm/worker/worker.py
+++ b/vllm/worker/worker.py
@@ -2,7 +2,7 @@
 """A GPU worker class."""
 import gc
 import os
-from typing import Dict, List, Optional, Set, Tuple, Type, Union
+from typing import Dict, List, Optional, Set, Tuple, Type, Union, TYPE_CHECKING, Any
 
 import torch
 import torch.distributed
@@ -31,6 +31,8 @@ from vllm.worker.model_runner import GPUModelRunnerBase, ModelRunner
 from vllm.worker.pooling_model_runner import PoolingModelRunner
 from vllm.worker.worker_base import (LocalOrDistributedWorkerBase, WorkerBase,
                                      WorkerInput)
3370
+from vllm.distributed.device_communicators.nixl import DynemoNixlConnector
ptarasiewiczNV's avatar
ptarasiewiczNV committed
3371
3372
3373
3374
3375
3376
3377
3378
3379
3380
3381
3382
3383
+
 
 logger = init_logger(__name__)
 
@@ -306,6 +308,43 @@ class Worker(LocalOrDistributedWorkerBase):
             self._init_cache_engine()
         self._warm_up_model()
 
+    def initialize_nixl(self, engine_id: str) -> List[bytes]:
+
+        # TODO ptarasiewicz nixl can also support DRAM
+        assert self.device_config.device_type == "cuda", "Currently only CUDA is supported for Nixl connector"
+
3384
+        self.nixl_connector = DynemoNixlConnector(self.vllm_config, engine_id, self.local_rank) # TODO ptarasiewicz: rank or local_rank?
ptarasiewiczNV's avatar
ptarasiewiczNV committed
3385
3386
3387
3388
3389
3390
3391
3392
3393
3394
+        assert len(self.cache_engine) == 1, "Only one cache engine is supported for now"
+        self.nixl_connector.register_kv_caches(self.cache_engine[0].gpu_cache)
+        return self.nixl_connector.agent_name
+    
+    def get_nixl_agent_metadata(self) -> bytes:
+        assert self.nixl_connector is not None, "Nixl connector is not initialized"
+        return self.nixl_connector.get_agent_metadata()
+
+    def add_remote_nixl_metadata(self, engine_id: str, agents_metadata: List[bytes], kv_caches_base_addr: List[List[Tuple[int, int]]]) -> str:
+        assert self.nixl_connector is not None, "Nixl connector is not initialized"
3395
3396
+        agent_name = self.nixl_connector.add_remote_agent(engine_id, agents_metadata[self.local_rank]) # TODO ptarasiewicz: rank or local_rank?
+        self.nixl_connector.add_remote_kv_caches_base_addr(engine_id, kv_caches_base_addr[self.local_rank])
ptarasiewiczNV's avatar
ptarasiewiczNV committed
3397
3398
3399
3400
+        return agent_name
+    
+    def transfer_nixl_memory(self, src_descs: List[bytes], dst_descs: List[bytes], remote_agent_name: List[str], notify_msg: str) -> None:
+        assert self.nixl_connector is not None, "Nixl connector is not initialized"
3401
+        self.nixl_connector.transfer_mem(src_descs[self.local_rank], dst_descs[self.local_rank], remote_agent_name[self.local_rank], notify_msg) # TODO ptarasiewicz: rank or local_rank?
ptarasiewiczNV's avatar
ptarasiewiczNV committed
3402
3403
3404
3405
3406
3407
3408
+
+    def get_nixl_kv_caches_base_addr(self) -> List[bytes]:
+        assert self.nixl_connector is not None, "Nixl connector is not initialized"
+        return self.nixl_connector.kv_caches_base_addr[self.nixl_connector.engine_id]
+        
+    def _transfer_blocks(self, worker_input: WorkerInput) -> None:
+        if worker_input.src_block_ids is not None:
3409
3410
+            for src_block_ids, dst_block_ids, dst_engine_id, notify_msg in zip(worker_input.src_block_ids, worker_input.dst_block_ids, worker_input.dst_engine_id, worker_input.notify_msg):
+                self.nixl_connector.transfer_mem(src_block_ids, dst_block_ids, dst_engine_id, notify_msg)
ptarasiewiczNV's avatar
ptarasiewiczNV committed
3411
3412
3413
3414
3415
3416
3417
3418
3419
3420
3421
3422
3423
3424
3425
3426
3427
+
+    def shutdown_nixl(self) -> None:
+        assert self.nixl_connector is not None, "Nixl connector is not initialized"
+        self.nixl_connector.shutdown()
+
     def _init_cache_engine(self):
         assert self.cache_config.num_gpu_blocks is not None
         self.cache_engine = [
@@ -367,6 +406,8 @@ class Worker(LocalOrDistributedWorkerBase):
         blocks_to_copy = torch.tensor(execute_model_req.blocks_to_copy,
                                       device=self.device,
                                       dtype=torch.int64).view(-1, 2)
+        
+        mem_transfer_reqs = execute_model_req.memory_transfer_requests or []
 
         return WorkerInput(
             num_seq_groups=num_seq_groups,
3428
@@ -375,6 +416,10 @@ class Worker(LocalOrDistributedWorkerBase):
ptarasiewiczNV's avatar
ptarasiewiczNV committed
3429
3430
3431
3432
3433
3434
3435
3436
3437
3438
3439
             blocks_to_copy=blocks_to_copy,
             virtual_engine=virtual_engine,
             num_steps=num_steps,
+            src_block_ids=[r.src_block_ids for r in mem_transfer_reqs],
+            dst_block_ids=[r.dst_block_ids for r in mem_transfer_reqs],
+            dst_engine_id=[r.dst_engine_id for r in mem_transfer_reqs],
+            notify_msg=[r.notify_msg for r in mem_transfer_reqs],
         )
 
     @torch.inference_mode()
diff --git a/vllm/worker/worker_base.py b/vllm/worker/worker_base.py
3440
index 819b81fb..d9c039eb 100644
ptarasiewiczNV's avatar
ptarasiewiczNV committed
3441
3442
3443
3444
3445
3446
3447
3448
3449
3450
3451
3452
3453
3454
--- a/vllm/worker/worker_base.py
+++ b/vllm/worker/worker_base.py
@@ -9,6 +9,7 @@ from typing import Any, Dict, List, Optional, Set, Tuple, Type, Union
 import cloudpickle
 import torch
 import torch.nn as nn
+from collections import defaultdict
 
 from vllm.config import (ObservabilityConfig, VllmConfig,
                          set_current_vllm_config)
@@ -23,6 +24,7 @@ from vllm.utils import (enable_trace_function_call_for_thread,
 from vllm.worker.model_runner_base import (BroadcastableModelInput,
                                            ModelRunnerBase,
                                            ModelRunnerInputBase)
3455
+from vllm.distributed.device_communicators.nixl import DynemoNixlConnector
ptarasiewiczNV's avatar
ptarasiewiczNV committed
3456
3457
3458
3459
3460
3461
3462
 
 logger = init_logger(__name__)
 
@@ -53,6 +55,8 @@ class WorkerBase(ABC):
         from vllm.platforms import current_platform
         self.current_platform = current_platform
 
3463
+        self.nixl_connector: Optional[DynemoNixlConnector] = None
ptarasiewiczNV's avatar
ptarasiewiczNV committed
3464
3465
3466
3467
+
     @abstractmethod
     def init_device(self) -> None:
         """Initialize device state, such as loading the model or other on-device
3468
@@ -216,6 +220,11 @@ class WorkerInput:
ptarasiewiczNV's avatar
ptarasiewiczNV committed
3469
3470
3471
3472
3473
3474
3475
3476
3477
3478
3479
     virtual_engine: int = 0
     num_steps: int = 1
 
+    src_block_ids: Optional[List[List[int]]] = None
+    dst_block_ids: Optional[List[List[int]]] = None
+    dst_engine_id: Optional[List[str]] = None
+    notify_msg: Optional[List[str]] = None
+
     @classmethod
     def from_broadcasted_tensor_dict(
         cls: Type["WorkerInput"],
3480
@@ -232,6 +241,10 @@ class WorkerInput:
ptarasiewiczNV's avatar
ptarasiewiczNV committed
3481
3482
3483
3484
3485
3486
3487
3488
3489
3490
             blocks_to_copy=tensor_dict.pop("blocks_to_copy"),
             virtual_engine=tensor_dict["virtual_engine"],
             num_steps=tensor_dict.pop("num_steps"),
+            src_block_ids=tensor_dict.pop("src_block_ids"),
+            dst_block_ids=tensor_dict.pop("dst_block_ids"),
+            dst_engine_id=tensor_dict.pop("dst_engine_id"),
+            notify_msg=tensor_dict.pop("notify_msg"),
         )
 
     def as_broadcastable_tensor_dict(
3491
@@ -246,6 +259,10 @@ class WorkerInput:
ptarasiewiczNV's avatar
ptarasiewiczNV committed
3492
3493
3494
3495
3496
3497
3498
3499
3500
3501
             "blocks_to_copy": self.blocks_to_copy,
             "virtual_engine": self.virtual_engine,
             "num_steps": self.num_steps,
+            "src_block_ids": self.src_block_ids,
+            "dst_block_ids": self.dst_block_ids,
+            "dst_engine_id": self.dst_engine_id,
+            "notify_msg": self.notify_msg,
         }
 
         return tensor_dict
3502
@@ -316,13 +333,16 @@ class LocalOrDistributedWorkerBase(WorkerBase):
ptarasiewiczNV's avatar
ptarasiewiczNV committed
3503
3504
3505
3506
3507
3508
3509
3510
3511
3512
3513
3514
3515
3516
3517
3518
3519
3520
3521
3522
3523
             return None
 
         worker_input = WorkerInput.from_broadcasted_tensor_dict(broadcast_data)
-        model_input = (
-            self.model_runner.make_model_input_from_broadcasted_tensor_dict(
-                broadcast_data))
+        if worker_input.num_seq_groups > 0:
+            model_input = (
+                self.model_runner.make_model_input_from_broadcasted_tensor_dict(
+                    broadcast_data))
 
-        kwargs = extract_previous_hidden_states(broadcast_data)
+            kwargs = extract_previous_hidden_states(broadcast_data)
 
-        return model_input, worker_input, kwargs
+            return model_input, worker_input, kwargs
+        else:
+            return None, worker_input, {}
 
     def _get_driver_input_and_broadcast(
         self, execute_model_req: ExecuteModelRequest
3524
@@ -396,49 +416,79 @@ class LocalOrDistributedWorkerBase(WorkerBase):
ptarasiewiczNV's avatar
ptarasiewiczNV committed
3525
3526
3527
3528
3529
3530
3531
3532
3533
3534
3535
3536
3537
3538
3539
3540
3541
3542
3543
3544
3545
3546
3547
3548
3549
3550
3551
3552
3553
3554
3555
3556
3557
3558
3559
3560
3561
3562
3563
3564
3565
3566
3567
3568
3569
3570
3571
3572
3573
3574
3575
3576
3577
3578
3579
3580
3581
3582
3583
3584
3585
3586
3587
3588
3589
3590
3591
3592
3593
3594
3595
3596
3597
3598
3599
3600
3601
3602
3603
3604
3605
3606
3607
3608
3609
3610
3611
3612
3613
3614
3615
3616
3617
3618
3619
3620
         self.execute_worker(worker_input)
 
         # If there is no input, we don't need to execute the model.
-        if worker_input.num_seq_groups == 0:
-            return []
-
-        intermediate_tensors = None
-        orig_model_execute_time = 0.0
-        if not get_pp_group().is_first_rank:
-            intermediate_tensors = IntermediateTensors(
-                get_pp_group().recv_tensor_dict(
-                    all_gather_group=get_tp_group()))
+        if worker_input.num_seq_groups > 0:
+
+            intermediate_tensors = None
+            orig_model_execute_time = 0.0
+            if not get_pp_group().is_first_rank:
+                intermediate_tensors = IntermediateTensors(
+                    get_pp_group().recv_tensor_dict(
+                        all_gather_group=get_tp_group()))
+                if (self.observability_config is not None
+                        and self.observability_config.collect_model_execute_time):
+                    orig_model_execute_time = intermediate_tensors.tensors.get(
+                        "model_execute_time", torch.tensor(0)).item()
+
+            output = self.model_runner.execute_model(
+                model_input=model_input,
+                kv_caches=self.kv_cache[worker_input.virtual_engine]
+                if self.kv_cache is not None else None,
+                intermediate_tensors=intermediate_tensors,
+                num_steps=num_steps,
+                **kwargs,
+            )
+
+            model_execute_time = time.perf_counter() - start_time
+            if not get_pp_group().is_last_rank:
+                # output is IntermediateTensors
+                assert isinstance(output, IntermediateTensors)
+                if (self.observability_config is not None
+                        and self.observability_config.collect_model_execute_time):
+                    output.tensors["model_execute_time"] = torch.tensor(
+                        model_execute_time + orig_model_execute_time)
+                get_pp_group().send_tensor_dict(output.tensors,
+                                                all_gather_group=get_tp_group())
+                return [None]
             if (self.observability_config is not None
-                    and self.observability_config.collect_model_execute_time):
-                orig_model_execute_time = intermediate_tensors.tensors.get(
-                    "model_execute_time", torch.tensor(0)).item()
+                    and self.observability_config.collect_model_execute_time
+                    and output is not None):
+                for o in output:
+                    o.model_execute_time = (orig_model_execute_time +
+                                            model_execute_time)
 
-        output = self.model_runner.execute_model(
-            model_input=model_input,
-            kv_caches=self.kv_cache[worker_input.virtual_engine]
-            if self.kv_cache is not None else None,
-            intermediate_tensors=intermediate_tensors,
-            num_steps=num_steps,
-            **kwargs,
-        )
+            self._transfer_blocks(worker_input)
 
-        model_execute_time = time.perf_counter() - start_time
-        if not get_pp_group().is_last_rank:
-            # output is IntermediateTensors
-            assert isinstance(output, IntermediateTensors)
-            if (self.observability_config is not None
-                    and self.observability_config.collect_model_execute_time):
-                output.tensors["model_execute_time"] = torch.tensor(
-                    model_execute_time + orig_model_execute_time)
-            get_pp_group().send_tensor_dict(output.tensors,
-                                            all_gather_group=get_tp_group())
-            return [None]
-        if (self.observability_config is not None
-                and self.observability_config.collect_model_execute_time
-                and output is not None):
-            for o in output:
-                o.model_execute_time = (orig_model_execute_time +
-                                        model_execute_time)
+        else:
+            output = []
+
+        # collect kv transfer notifications from non driver workers
+
+        if self.nixl_connector is not None:
+            new_notifs = self.nixl_connector.get_new_notifs()
+            rank = get_tp_group().rank
+            all_new_notifs = [new_notifs]
+            if rank > 0:
+                get_tp_group().send_object(new_notifs, dst=0)
+            else:
+                for i in range(1, get_tp_group().world_size):
+                    all_new_notifs.append(get_tp_group().recv_object(src=i))
3621
+
ptarasiewiczNV's avatar
ptarasiewiczNV committed
3622
3623
3624
3625
3626
3627
3628
3629
3630
3631
+            request_notif_counter = defaultdict(int)
+            for notifs in all_new_notifs:
+                for req_ids in notifs.values():
+                    for req_id in req_ids:
+                        request_notif_counter[req_id] += 1
+
+            if request_notif_counter:
+                logger.debug("Request notif counter: %s", request_notif_counter)
+        else:
+            request_notif_counter = {}
3632
 
ptarasiewiczNV's avatar
ptarasiewiczNV committed
3633
3634
         # output is List[SamplerOutput]
-        return output
3635
+        return output, request_notif_counter
ptarasiewiczNV's avatar
ptarasiewiczNV committed
3636
3637
3638
3639
3640
3641
+    
+    def _transfer_blocks(self, worker_input: WorkerInput) -> None:
+        pass
 
     def _execute_model_spmd(
         self,