[core][distributed] zmq fallback for broadcasting large objects (#6183)

[core][distributed] add zmq fallback for broadcasting large objects (#6183)

tests/distributed/test_shm_broadcast.py

@@ -6,8 +6,7 @@ from typing import List
 import numpy as np
 import torch.distributed as dist
 
-from vllm.distributed.device_communicators.shm_broadcast import (
-    ShmRingBuffer, ShmRingBufferIO)
+from vllm.distributed.device_communicators.shm_broadcast import MessageQueue
 from vllm.utils import update_environment_variables
 
 
@@ -56,8 +55,8 @@ def worker_fn_wrapper(fn):
 @worker_fn_wrapper
 def worker_fn():
     writer_rank = 2
-    broadcaster = ShmRingBufferIO.create_from_process_group(
-        dist.group.WORLD, 1024 * 1024, 2, writer_rank)
+    broadcaster = MessageQueue.create_from_process_group(
+        dist.group.WORLD, 40 * 1024, 2, writer_rank)
     if dist.get_rank() == writer_rank:
         seed = random.randint(0, 1000)
         dist.broadcast_object_list([seed], writer_rank)
@@ -87,13 +86,3 @@ def worker_fn():
 
 def test_shm_broadcast():
     distributed_run(worker_fn, 4)
-
-
-def test_singe_process():
-    buffer = ShmRingBuffer(1, 1024, 4)
-    reader = ShmRingBufferIO(buffer, reader_rank=0)
-    writer = ShmRingBufferIO(buffer, reader_rank=-1)
-    writer.enqueue([0])
-    writer.enqueue([1])
-    assert reader.dequeue() == [0]
-    assert reader.dequeue() == [1]