[PD] bug fix: Update status if nixl receiver send a a dummy req. (#6720)

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

@@ -53,26 +53,10 @@ class TransferInfo:
     required_dst_info_num: int
 
     def is_dummy(self):
-        return self.endpoint == ""
+        return self.dst_kv_indices.size == 0
 
     @classmethod
     def from_zmq(cls, msg: List[bytes]):
-        if len(msg) == 1:
-            # dummy msg
-            return cls(
-                room=int(msg[0].decode("ascii")),
-                endpoint="",
-                dst_port=0,
-                agent_metadata=b"",
-                agent_name="",
-                dst_kv_ptrs=[],
-                dst_kv_indices=np.array([], dtype=np.int64),
-                dst_aux_ptrs=[],
-                dst_aux_index=0,
-                dst_gpu_id=0,
-                required_dst_info_num=0,
-            )
-        else:
         return cls(
             room=int(msg[0].decode("ascii")),
             endpoint=msg[1].decode("ascii"),
@@ -278,7 +262,7 @@ class NixlKVManager(CommonKVManager):
         for req in reqs_to_be_processed:
             assert bootstrap_room == req.room
             if req.is_dummy():
-                return []
+                continue
 
             peer_name = self._add_remote(req.agent_name, req.agent_metadata)
             chunked_dst_kv_indice = req.dst_kv_indices[index_slice]
@@ -346,8 +330,7 @@ class NixlKVManager(CommonKVManager):
                 ), f"First message should be {GUARD}. Foreign traffic?"
                 waiting_req_bytes = waiting_req_bytes[1:]
                 room = waiting_req_bytes[0].decode("ascii")
-                if room == "None":
-                    continue
+
                 required_dst_info_num = int(waiting_req_bytes[10].decode("ascii"))
                 room = int(room)
                 agent_name = waiting_req_bytes[4].decode("ascii")
@@ -438,19 +421,6 @@ class NixlKVReceiver(CommonKVReceiver):
             )
             is_dummy = bootstrap_info["is_dummy"]
 
-            # TODO: just send "" for indices for dummy
-            if is_dummy:
-                # TODO: need to set success??
-                sock, lock = self._connect("tcp://" + self.prefill_server_url)
-                with lock:
-                    sock.send_multipart(
-                        [
-                            GUARD,
-                            str(self.bootstrap_room).encode("ascii"),
-                        ]
-                    )
-                continue
-
             # TODO: send_kv_args earlier
             packed_kv_data_ptrs = b"".join(
                 struct.pack("Q", ptr) for ptr in self.kv_mgr.kv_args.kv_data_ptrs
@@ -473,7 +443,7 @@ class NixlKVReceiver(CommonKVReceiver):
                         self.kv_mgr.agent.get_agent_metadata(),
                         self.kv_mgr.agent.name.encode("ascii"),
                         packed_kv_data_ptrs,
-                        kv_indices.tobytes(),
+                        kv_indices.tobytes() if not is_dummy else b"",
                         packed_aux_data_ptrs,
                         str(aux_index).encode("ascii"),
                         str(self.kv_mgr.kv_args.gpu_id).encode("ascii"),