[Core] Optimize SPMD architecture with delta + serialization optimization (#7109)

vllm/executor/msgspec_utils.py

@@ -0,0 +1,27 @@
+from array import array
+from typing import Any, Type
+
+from vllm.sequence import VLLM_TOKEN_ID_ARRAY_TYPE
+
+
+def encode_hook(obj: Any) -> Any:
+    """Custom msgspec enc hook that supports array types.
+
+    See https://jcristharif.com/msgspec/api.html#msgspec.msgpack.Encoder
+    """
+    if isinstance(obj, array):
+        assert obj.typecode == VLLM_TOKEN_ID_ARRAY_TYPE, (
+            f"vLLM array type should use '{VLLM_TOKEN_ID_ARRAY_TYPE}' type. "
+            f"Given array has a type code of {obj.typecode}.")
+        return obj.tobytes()
+
+
+def decode_hook(type: Type, obj: Any) -> Any:
+    """Custom msgspec dec hook that supports array types.
+
+    See https://jcristharif.com/msgspec/api.html#msgspec.msgpack.Encoder
+    """
+    if type is array:
+        deserialized = array(VLLM_TOKEN_ID_ARRAY_TYPE)
+        deserialized.frombytes(obj)
+        return deserialized