[Frontend] error suppression cleanup (#7786)

Signed-off-by: Joe Runde <Joseph.Runde@ibm.com>

tests/entrypoints/openai/rpc/test_zmq_client.py

@@ -75,10 +75,11 @@ async def test_client_aborts_use_timeouts(monkeypatch, dummy_server,
         m.setattr(dummy_server, "abort", lambda x: None)
         m.setattr(client, "_data_timeout", 10)
 
-        # Ensure the client doesn't hang
+        # The client should suppress timeouts on `abort`s
+        # and return normally, assuming the server will eventually
+        # abort the request.
         client_task = asyncio.get_running_loop().create_task(
             client.abort("test request id"))
-        with pytest.raises(TimeoutError, match="Server didn't reply within"):
         await asyncio.wait_for(client_task, timeout=0.05)
 
 

vllm/entrypoints/openai/api_server.py

@@ -6,7 +6,7 @@ import os
 import re
 import tempfile
 from argparse import Namespace
-from contextlib import asynccontextmanager, suppress
+from contextlib import asynccontextmanager
 from http import HTTPStatus
 from typing import AsyncIterator, Optional, Set
 
@@ -83,7 +83,6 @@ async def lifespan(app: FastAPI):
     async def _force_log():
         while True:
             await asyncio.sleep(10)
-            with suppress(Exception):
             await async_engine_client.do_log_stats()
 
     if not engine_args.disable_log_stats:

vllm/entrypoints/openai/rpc/client.py

@@ -335,7 +335,18 @@ class AsyncEngineRPCClient:
 
     async def abort(self, request_id: str):
         """Send an ABORT_REQUEST signal to the RPC Server"""
-        with suppress(RPCClientClosedError):
+
+        # Suppress timeouts as well.
+        # In cases where the server is busy processing requests and a very
+        # large volume of abort requests arrive, it is likely that the server
+        # will not be able to ack all of them in time. We have seen this when
+        # we abort 20k requests at once while another 2k are processing- many
+        # of them time out, but we see the server successfully abort all of the
+        # requests.
+        # In this case we assume that the server has received or will receive
+        # these abort requests, and ignore the timeout. This prevents a massive
+        # wall of `TimeoutError` stack traces.
+        with suppress(RPCClientClosedError, TimeoutError):
             await self._send_one_way_rpc_request(
                 request=RPCAbortRequest(request_id),
                 error_message=f"RPCAbortRequest {request_id} failed")