[PD] Add support for dp attention with mooncake (#5530)

Signed-off-by: Shangming Cai <caishangming@linux.alibaba.com>

python/sglang/srt/disaggregation/mooncake/conn.py

@@ -109,6 +109,13 @@ class MooncakeKVManager(BaseKVManager):
         # for p/d multi node infer
         self.bootstrap_port = server_args.disaggregation_bootstrap_port
         self.dist_init_addr = server_args.dist_init_addr
+        self.tp_size = server_args.tp_size
+        self.dp_size = server_args.dp_size
+        self.enable_dp_attention = server_args.enable_dp_attention
+        if not server_args.enable_dp_attention and server_args.dp_size != 1:
+            raise ValueError(
+                "If dp_attention is not enabled, dp size must be 1 in disaggregation mode."
+            )
         self.request_status: Dict[int, KVPoll] = {}
         self.rank_port = None
         self.server_socket = zmq.Context().socket(zmq.PULL)
@@ -121,6 +128,7 @@ class MooncakeKVManager(BaseKVManager):
         elif self.disaggregation_mode == DisaggregationMode.DECODE:
             self.start_decode_thread()
             self.connection_pool: Dict[str, Dict[str, Union[str, int]]] = {}
+            self.prefill_dp_size_table: Dict[str, int] = {}
         else:
             raise ValueError(
                 f"Unsupported DisaggregationMode: {self.disaggregation_mode}"
@@ -331,6 +339,8 @@ class MooncakeKVManager(BaseKVManager):
         url = f"http://{bootstrap_server_url}/route"
         payload = {
             "role": "Prefill",
+            "tp_size": self.tp_size,
+            "dp_size": self.dp_size,
             "rank_ip": get_local_ip_by_remote(),
             "rank_port": self.rank_port,
             "engine_rank": self.kv_args.engine_rank,
@@ -408,12 +418,41 @@ class MooncakeKVReceiver(BaseKVReceiver):
         self.session_id = self.kv_mgr.get_session_id()
         self.kv_mgr.update_status(bootstrap_room, KVPoll.Bootstrapping)
 
+        if not self.kv_mgr.enable_dp_attention:
+            # We assume dp_attention should be activated simultaneously for
+            # both prefill role and decode role. If the decode instance does
+            # not enable dp_attention, then dp_attention is not enabled on the
+            # prefill instance as well. Therefore, we should skip questioning
+            # the prefill dp size to reduce bootstrap overhead.
+            self.prefill_dp_size = 1
+        elif self.bootstrap_addr not in self.kv_mgr.prefill_dp_size_table:
+            self.prefill_dp_size, tp_size_per_dp_rank = (
+                self._get_prefill_dp_size_from_server()
+            )
+            # Currently, we don't allow prefill instance and decode instance to
+            # have different TP sizes per DP rank.
+            assert tp_size_per_dp_rank == self.kv_mgr.tp_size // self.kv_mgr.dp_size
+            if self.prefill_dp_size is None:
+                logger.error(
+                    f"Could not fetch prefill dp_size for bootstrap_addr: {self.bootstrap_addr}"
+                )
+            else:
+                self.kv_mgr.prefill_dp_size_table[self.bootstrap_addr] = (
+                    self.prefill_dp_size
+                )
+        else:
+            self.prefill_dp_size = self.kv_mgr.prefill_dp_size_table[
+                self.bootstrap_addr
+            ]
+
         # NOTE: key distinguished by bootstrap_addr and engine_rank
+        self.target_dp_group = bootstrap_room % self.prefill_dp_size
         bootstrap_key = f"{self.bootstrap_addr}_{self.kv_mgr.kv_args.engine_rank}"
 
         if bootstrap_key not in self.kv_mgr.connection_pool:
             self.bootstrap_info = self._get_bootstrap_info_from_server(
-                self.kv_mgr.kv_args.engine_rank
+                self.kv_mgr.kv_args.engine_rank,
+                self.target_dp_group,
             )
             if self.bootstrap_info is None:
                 logger.error(
@@ -427,10 +466,10 @@ class MooncakeKVReceiver(BaseKVReceiver):
         assert self.bootstrap_info is not None
         self.kv_mgr.update_status(bootstrap_room, KVPoll.WaitingForInput)
 
-    def _get_bootstrap_info_from_server(self, engine_rank):
+    def _get_bootstrap_info_from_server(self, engine_rank, target_dp_group):
         """Fetch the bootstrap info from the bootstrap server."""
         try:
-            url = f"http://{self.bootstrap_addr}/route?engine_rank={engine_rank}"
+            url = f"http://{self.bootstrap_addr}/route?engine_rank={engine_rank}&target_dp_group={target_dp_group}"
             response = requests.get(url)
             if response.status_code == 200:
                 bootstrap_info = response.json()
@@ -444,6 +483,25 @@ class MooncakeKVReceiver(BaseKVReceiver):
             logger.error(f"Error fetching prefill info from bootstrap: {e}")
             return None
 
+    def _get_prefill_dp_size_from_server(self) -> int:
+        """Fetch the prefill parallel info from the bootstrap server."""
+        try:
+            url = f"http://{self.bootstrap_addr}/route?engine_rank={-1}&target_dp_group={-1}"
+            response = requests.get(url)
+            if response.status_code == 200:
+                prefill_parallel_info = response.json()
+                return int(prefill_parallel_info["prefill_dp_size"]), int(
+                    prefill_parallel_info["tp_size_per_dp_rank"]
+                )
+            else:
+                logger.error(
+                    f"Failed to get prefill parallel info: {response.status_code}, {response.text}"
+                )
+                return None
+        except Exception as e:
+            logger.error(f"Error fetching prefill parallel info from bootstrap: {e}")
+            return None
+
     @classmethod
     def _connect(cls, endpoint: str):
         with cls._global_lock:
@@ -497,7 +555,9 @@ class MooncakeKVBootstrapServer(BaseKVBootstrapServer):
         self.store = dict()
         self.lock = asyncio.Lock()
         self._setup_routes()
-        self.prefill_port_table: Dict[int, Dict[str, Union[str, int]]] = {}
+        self.dp_size = None
+        self.tp_size_per_dp_rank = None
+        self.prefill_port_table: Dict[int, Dict[int, Dict[str, Union[str, int]]]] = {}
 
         # Start bootstrap server
         self.thread = threading.Thread(target=self._run_server, daemon=True)
@@ -523,35 +583,64 @@ class MooncakeKVBootstrapServer(BaseKVBootstrapServer):
     async def _handle_route_put(self, request: web.Request):
         data = await request.json()
         role = data["role"]
+        tp_size = data["tp_size"]
+        dp_size = data["dp_size"]
         rank_ip = data["rank_ip"]
         rank_port = int(data["rank_port"])
         engine_rank = int(data["engine_rank"])
 
+        if self.dp_size is None:
+            self.dp_size = dp_size
+
+        tp_size_per_dp_rank = tp_size // dp_size
+        if self.tp_size_per_dp_rank == None:
+            self.tp_size_per_dp_rank = tp_size_per_dp_rank
+
         # Add lock to make sure thread-safe
         if role == "Prefill":
-            self.prefill_port_table[engine_rank] = {
+            dp_group = engine_rank // tp_size_per_dp_rank
+            tp_rank_in_dp_group = engine_rank % tp_size_per_dp_rank
+
+            async with self.lock:
+                if dp_group not in self.prefill_port_table:
+                    self.prefill_port_table[dp_group] = {}
+
+            self.prefill_port_table[dp_group][tp_rank_in_dp_group] = {
                 "rank_ip": rank_ip,
                 "rank_port": rank_port,
             }
             logger.debug(
-                f"Registered Prefill boostrap: {engine_rank} with rank_ip: {rank_ip} and rank_port: {rank_port}"
+                f"Registered Prefill bootstrap: {engine_rank} with rank_ip: {rank_ip} and rank_port: {rank_port}"
             )
 
         return web.Response(text="OK", status=200)
 
     async def _handle_route_get(self, request: web.Request):
         engine_rank = request.query.get("engine_rank")
-        if not engine_rank:
-            return web.Response(text="Missing rank", status=400)
+        target_dp_group = request.query.get("target_dp_group")
+        if not engine_rank or not target_dp_group:
+            return web.Response(text="Missing inputs for bootstrap server.", status=400)
+
+        # Currently we use engine_rank == -1 and target_dp_group == -1 to sync dp size
+        if int(engine_rank) == -1 and int(target_dp_group) == -1:
+            prefill_parallel_info = {
+                "prefill_dp_size": self.dp_size,
+                "tp_size_per_dp_rank": self.tp_size_per_dp_rank,
+            }
+            return web.json_response(prefill_parallel_info, status=200)
 
         # Find corresponding prefill info
+        tp_rank_in_dp_group = int(engine_rank) % self.tp_size_per_dp_rank
+
         async with self.lock:
-            bootstrap_info = self.prefill_port_table.get(int(engine_rank))
+            bootstrap_info = self.prefill_port_table[int(target_dp_group)][
+                tp_rank_in_dp_group
+            ]
 
         if bootstrap_info is not None:
             return web.json_response(bootstrap_info, status=200)
         else:
-            return web.Response(text="Not Found", status=404)
+            return web.Response(text="Bootstrap info not Found", status=404)
 
     def _run_server(self):
         try: