[V1] VLM - Run the mm_mapper preprocessor in the frontend process (#10640)

Signed-off-by: Roger Wang <ywang@roblox.com>
Co-authored-by: Michael Goin <michael@neuralmagic.com>
Co-authored-by: Roger Wang <ywang@roblox.com>

tests/v1/engine/test_engine_core.py

@@ -27,9 +27,8 @@ def make_request() -> EngineCoreRequest:
         request_id=uuid.uuid4(),
         prompt=PROMPT,
         prompt_token_ids=PROMPT_TOKENS,
-        mm_data=None,
+        mm_inputs=None,
         mm_placeholders=None,
-        mm_processor_kwargs=None,
         sampling_params=SamplingParams(),
         eos_token_id=None,
         arrival_time=time.time(),

tests/v1/engine/test_engine_core_client.py

@@ -29,9 +29,8 @@ def make_request(params: SamplingParams) -> EngineCoreRequest:
         request_id=str(uuid.uuid4()),
         prompt=PROMPT,
         prompt_token_ids=PROMPT_TOKENS,
-        mm_data=None,
+        mm_inputs=None,
         mm_placeholders=None,
-        mm_processor_kwargs=None,
         sampling_params=params,
         eos_token_id=None,
         arrival_time=time.time(),

vllm/inputs/data.py

@@ -7,7 +7,8 @@ import torch
 from typing_extensions import NotRequired, TypedDict, TypeVar, assert_never
 
 if TYPE_CHECKING:
-    from vllm.multimodal import MultiModalDataDict, MultiModalPlaceholderDict
+    from vllm.multimodal import (MultiModalDataDict, MultiModalKwargs,
+                                 MultiModalPlaceholderDict)
     from vllm.multimodal.inputs import MultiModalInputsV2
 
 
@@ -150,6 +151,12 @@ class TokenInputs(TypedDict):
     if the model supports it.
     """
 
+    multi_modal_inputs: NotRequired["MultiModalKwargs"]
+    """
+    Optional multi-modal inputs to pass to the model,
+    if the model supports it.
+    """
+
     multi_modal_placeholders: NotRequired["MultiModalPlaceholderDict"]
     """
     Placeholder ranges for the multi-modal data.
@@ -169,6 +176,7 @@ def token_inputs(
     token_type_ids: Optional[List[int]] = None,
     prompt: Optional[str] = None,
     multi_modal_data: Optional["MultiModalDataDict"] = None,
+    multi_modal_inputs: Optional["MultiModalKwargs"] = None,
     multi_modal_placeholders: Optional["MultiModalPlaceholderDict"] = None,
     mm_processor_kwargs: Optional[Dict[str, Any]] = None,
 ) -> TokenInputs:
@@ -181,6 +189,8 @@ def token_inputs(
         inputs["token_type_ids"] = token_type_ids
     if multi_modal_data is not None:
         inputs["multi_modal_data"] = multi_modal_data
+    if multi_modal_inputs is not None:
+        inputs["multi_modal_inputs"] = multi_modal_inputs
     if multi_modal_placeholders is not None:
         inputs["multi_modal_placeholders"] = multi_modal_placeholders
     if mm_processor_kwargs is not None:
@@ -273,6 +283,18 @@ class SingletonInputsAdapter:
 
         assert_never(inputs)
 
+    @cached_property
+    def multi_modal_inputs(self) -> Union[Dict, "MultiModalKwargs"]:
+        inputs = self.inputs
+
+        if inputs["type"] == "token":
+            return inputs.get("multi_modal_inputs", {})
+
+        if inputs["type"] == "multimodal":
+            return inputs.get("mm_kwargs", {})
+
+        assert_never(inputs)
+
     @cached_property
     def multi_modal_placeholders(self) -> "MultiModalPlaceholderDict":
         inputs = self.inputs

vllm/v1/engine/__init__.py

 import enum
 from dataclasses import dataclass
-from typing import Any, Dict, List, Optional, Union
+from typing import List, Optional, Union
 
 import msgspec
 
 from vllm.lora.request import LoRARequest
-from vllm.multimodal import MultiModalDataDict, MultiModalPlaceholderDict
+from vllm.multimodal import MultiModalKwargs, MultiModalPlaceholderDict
 from vllm.sampling_params import RequestOutputKind, SamplingParams
 
 
@@ -35,9 +35,8 @@ class EngineCoreRequest:
     # always be tokenized?
     prompt: Optional[str]
     prompt_token_ids: List[int]
-    mm_data: Optional[MultiModalDataDict]
+    mm_inputs: Optional[List[MultiModalKwargs]]
     mm_placeholders: Optional[MultiModalPlaceholderDict]
-    mm_processor_kwargs: Optional[Dict[str, Any]]
     sampling_params: SamplingParams
     eos_token_id: Optional[int]
     arrival_time: float

vllm/v1/engine/core.py

@@ -84,14 +84,7 @@ class EngineCore:
 
     def add_request(self, request: EngineCoreRequest):
         """Add request to the scheduler."""
-
         req = Request.from_engine_core_request(request)
-        # FIXME(woosuk): The input mapping (e.g., PIL images to tensors) may
-        # take 10-50 ms, which can cause a spike in the latency. We should
-        # consider moving this to a separate thread.
-        if req.mm_data:
-            req.mm_inputs = self.mm_input_mapper.process_inputs(
-                req.mm_data, req.mm_processor_kwargs)
         self.scheduler.add_request(req)
 
     def abort_requests(self, request_ids: List[str]):

vllm/v1/engine/processor.py

@@ -14,6 +14,7 @@ from vllm.sampling_params import SamplingParams
 from vllm.transformers_utils.config import try_get_generation_config
 from vllm.transformers_utils.tokenizer_group import BaseTokenizerGroup
 from vllm.v1.engine import DetokenizerRequest, EngineCoreRequest
+from vllm.v1.engine.mm_input_mapper import MMInputMapper
 
 
 class Processor:
@@ -39,6 +40,9 @@ class Processor:
         self.input_processor = input_registry.create_input_processor(
             model_config)
 
+        # Multi-modal (huggingface) input mapper
+        self.mm_input_mapper = MMInputMapper(model_config)
+
     # TODO: run in an ThreadpoolExecutor or BackgroundProcess.
     # This ideally should releases the GIL, so we should not block the
     # asyncio loop while this is running.
@@ -96,6 +100,12 @@ class Processor:
         sampling_params.update_from_generation_config(
             self.generation_config_fields, eos_token_id)
 
+        # Preprocess multi-modal data
+        mm_inputs = self.mm_input_mapper.process_inputs(
+            decoder_inputs.multi_modal_data,
+            decoder_inputs.mm_processor_kwargs) if len(
+                decoder_inputs.multi_modal_data) > 0 else None
+
         # Make Request for Detokenizer.
         detokenizer_request = DetokenizerRequest(
             request_id,
@@ -113,9 +123,8 @@ class Processor:
             request_id,
             decoder_inputs.prompt,
             decoder_inputs.prompt_token_ids,
-            decoder_inputs.multi_modal_data,
+            mm_inputs,
             decoder_inputs.multi_modal_placeholders,
-            decoder_inputs.mm_processor_kwargs,
             sampling_params,
             eos_token_id,
             arrival_time,

vllm/v1/request.py

@@ -45,9 +45,6 @@ class Request:
         self._all_token_ids: List[int] = self.prompt_token_ids.copy()
         self.num_computed_tokens = 0
 
-        # Raw multimodal data before the mm input mapper (e.g., PIL images).
-        self.mm_data = self.inputs.multi_modal_data
-        self.mm_processor_kwargs = self.inputs.mm_processor_kwargs
         mm_positions = self.inputs.multi_modal_placeholders
         if mm_positions:
             # FIXME(woosuk): Support other modalities.
@@ -55,6 +52,9 @@ class Request:
         else:
             self.mm_positions = []
         # Output of the mm input mapper (e.g., image tensors).
+        if self.inputs.multi_modal_inputs:
+            self.mm_inputs = self.inputs.multi_modal_inputs
+        else:
             self.mm_inputs: List[MultiModalKwargs] = []
 
     @classmethod
@@ -64,9 +64,10 @@ class Request:
             inputs=token_inputs(
                 prompt_token_ids=request.prompt_token_ids,
                 prompt=request.prompt,
-                multi_modal_data=request.mm_data,
+                multi_modal_data=None,
+                multi_modal_inputs=request.mm_inputs,
                 multi_modal_placeholders=request.mm_placeholders,
-                mm_processor_kwargs=request.mm_processor_kwargs,
+                mm_processor_kwargs=None,
             ),
             sampling_params=request.sampling_params,
             eos_token_id=request.eos_token_id,
@@ -110,7 +111,7 @@ class Request:
         return RequestStatus.get_finished_reason(self.status)
 
     def has_encoder_inputs(self) -> bool:
-        return len(self.mm_data) > 0
+        return len(self.mm_inputs) > 0
 
     @property
     def num_encoder_inputs(self) -> int: