[Bugfix] Preserve session IDs when upgrading Omni engine requests

Signed-off-by: tzhouam <tzhouam@connect.ust.hk>

tests/engine/test_omni_request.py

@@ -13,13 +13,15 @@ substitutable with the base class — including base-style calls that pass
 
 import inspect
 
+import msgspec
 import numpy as np
 import pytest
 import torch
 from vllm.sampling_params import SamplingParams
+from vllm.v1.engine import EngineCoreRequest
 from vllm.v1.request import Request
 
-from vllm_omni.engine import PromptEmbedsPayload
+from vllm_omni.engine import OmniEngineCoreRequest, PromptEmbedsPayload
 from vllm_omni.request import OmniRequest, OmniStreamingUpdate
 
 pytestmark = [pytest.mark.core_model, pytest.mark.cpu]
@@ -111,3 +113,24 @@ def test_model_intermediate_buffer_round_trips_to_streaming_update():
     assert update is not None
     assert request.model_intermediate_buffer is buffer
     assert update.model_intermediate_buffer is buffer
+
+
+@pytest.mark.parametrize("session_id", [None, "session"])
+def test_session_survives_omni_upgrade_wire_transport_and_scheduler_conversion(session_id):
+    core = EngineCoreRequest(
+        request_id="session-request",
+        prompt_token_ids=[1, 2],
+        mm_features=None,
+        sampling_params=SamplingParams(max_tokens=2),
+        pooling_params=None,
+        arrival_time=0.0,
+        lora_request=None,
+        cache_salt=None,
+        data_parallel_rank=None,
+        session_id=session_id,
+    )
+    upgraded = OmniEngineCoreRequest.from_request(core)
+    decoded = msgspec.msgpack.decode(msgspec.msgpack.encode(upgraded), type=OmniEngineCoreRequest)
+    scheduled = OmniRequest.from_engine_core_request(decoded, block_hasher=None)
+    assert decoded.session_id == session_id
+    assert scheduled.session_id == session_id

tests/helpers/runtime.py

@@ -659,14 +659,6 @@ class OmniRunner:
         self.seed = seed
         self._prompt_len_estimate_cache: dict[str, Any] = {}
         self.omni: Any = None
-        self._runner_process = psutil.Process()
-        self._initial_child_ids: set[tuple[int, float]] = set()
-        self._owned_engine_processes: dict[int, float] = {}
-        for child in self._runner_process.children(recursive=True):
-            try:
-                self._initial_child_ids.add((child.pid, child.create_time()))
-            except psutil.Error:
-                pass
         try:
             from vllm_omni.entrypoints.omni import Omni
 
@@ -678,14 +670,12 @@ class OmniRunner:
                 deploy_config=deploy_config,
                 **kwargs,
             )
-            self._remember_engine_processes(startup=True)
             startup_s = time.perf_counter() - startup_t0
             if log_stats:
                 print(f"OmniRunner startup took {startup_s:.3f}s (model={model_name})", flush=True)
         except BaseException:
             # ``with OmniRunner(...)`` never reaches ``__enter__``/``__exit__``
             # when construction fails after worker processes have started.
-            self._remember_engine_processes(startup=True)
             self.__exit__(None, None, None)
             raise
 
@@ -909,51 +899,18 @@ class OmniRunner:
     def stop_profile(self, stages: list[int] | None = None) -> list[Any]:
         return self.omni.stop_profile(stages=stages)
 
-    def _remember_engine_processes(self, *, startup: bool = False) -> None:
-        """Track startup workers, then only descendants of those workers.
-
-        Existing children may belong to another runner or a shared transcriber.
-        Record identities before close() can reparent surviving workers.
-        """
-        try:
-            if startup:
-                candidates = self._runner_process.children(recursive=True)
-            else:
-                candidates = []
-                for pid, created in list(self._owned_engine_processes.items()):
-                    try:
-                        proc = psutil.Process(pid)
-                        if proc.create_time() == created:
-                            candidates.extend(proc.children(recursive=True))
-                    except psutil.Error:
-                        pass
-            for proc in candidates:
-                try:
-                    identity = (proc.pid, proc.create_time())
-                    if identity in self._initial_child_ids:
-                        continue
-                    if startup and any(
-                        (parent.pid, parent.create_time()) in self._initial_child_ids for parent in proc.parents()
-                    ):
-                        continue
-                    cmdline = " ".join(proc.cmdline()).lower()
-                    if "enginecore" in cmdline or "enginecore" in proc.name().lower():
-                        self._owned_engine_processes[identity[0]] = identity[1]
-                except psutil.Error:
-                    pass
-        except psutil.Error as error:
-            print(f"Warning: could not inspect runner workers: {error}")
-
     def _cleanup_process(self):
         try:
+            keywords = ["enginecore"]
             matched = []
-            for pid, created in self._owned_engine_processes.items():
+            for proc in psutil.process_iter(["pid", "name", "cmdline", "username"]):
                 try:
-                    proc = psutil.Process(pid)
+                    cmdline = " ".join(proc.cmdline()).lower() if proc.cmdline() else ""
-                    if proc.create_time() == created:
+                    name = proc.name().lower()
-                        print(f"Found owned vllm process: PID={proc.pid}")
+                    if any(k in cmdline for k in keywords) or any(k in name for k in keywords):
+                        print(f"Found vllm process: PID={proc.pid}, cmd={cmdline[:100]}")
                         matched.append(proc)
-                except psutil.Error:
+                except (psutil.NoSuchProcess, psutil.AccessDenied):
                     pass
             for proc in matched:
                 try:
@@ -981,14 +938,11 @@ class OmniRunner:
         return self
 
     def __exit__(self, exc_type, exc_val, exc_tb):
-        self._remember_engine_processes()
+        omni = getattr(self, "omni", None)
-        try:
+        if omni is not None and hasattr(omni, "close"):
-            omni = getattr(self, "omni", None)
+            omni.close()
-            if omni is not None and hasattr(omni, "close"):
+        self._cleanup_process()
-                omni.close()
+        cleanup_test_environment()
-        finally:
-            self._cleanup_process()
-            cleanup_test_environment()
 
 
 # ---------------------------------------------------------------------------

tests/helpers/tests/test_runtime_omni_runner.py

@@ -1,15 +1,10 @@
 # SPDX-License-Identifier: Apache-2.0
 # SPDX-FileCopyrightText: Copyright contributors to the vLLM-Omni project
 
-"""Tests for OmniRunner startup rollback and worker ownership."""
+"""Tests for OmniRunner startup rollback."""
 
 from __future__ import annotations
 
-import subprocess
-import sys
-from collections.abc import Generator
-
-import psutil
 import pytest
 
 from tests.helpers.runtime import OmniRunner
@@ -43,114 +38,3 @@ def test_runner_init_rolls_back_on_omni_startup_failure(monkeypatch: pytest.Monk
     assert cleaned.count("process") == 1
     # Once at the start of ``__init__``, once from the constructor rollback.
     assert cleaned.count("env") == 2
-
-
-@pytest.fixture
-def live_workers() -> Generator[list[subprocess.Popen[bytes]], None, None]:
-    workers: list[subprocess.Popen[bytes]] = []
-    try:
-        yield workers
-    finally:
-        for worker in workers:
-            if worker.poll() is None:
-                worker.kill()
-            worker.wait(timeout=10)
-            if worker.stdout is not None:
-                worker.stdout.close()
-
-
-def _start_engine_worker(
-    workers: list[subprocess.Popen[bytes]], *, ignore_terminate: bool = False
-) -> subprocess.Popen[bytes]:
-    script = "import signal, time; "
-    if ignore_terminate:
-        script += "signal.signal(signal.SIGTERM, signal.SIG_IGN); "
-    script += "print('ready', flush=True); time.sleep(90)"
-    worker = subprocess.Popen([sys.executable, "-c", script, "enginecore"], stdout=subprocess.PIPE)
-    workers.append(worker)
-    assert worker.stdout is not None
-    assert worker.stdout.readline() == b"ready\n"
-    return worker
-
-
-@pytest.mark.parametrize("close_raises", [False, True])
-def test_runner_cleanup_preserves_unrelated_engine_workers(
-    monkeypatch: pytest.MonkeyPatch,
-    live_workers: list[subprocess.Popen[bytes]],
-    close_raises: bool,
-) -> None:
-    existing = _start_engine_worker(live_workers)
-    owned: list[subprocess.Popen[bytes]] = []
-    late_unrelated: list[subprocess.Popen[bytes]] = []
-    monkeypatch.setattr("tests.helpers.runtime.cleanup_test_environment", lambda: None)
-
-    class _OwnedOmni:
-        def __init__(self, *args: object, **kwargs: object) -> None:
-            owned.append(_start_engine_worker(live_workers))
-
-        def close(self) -> None:
-            late_unrelated.append(_start_engine_worker(live_workers))
-            if close_raises:
-                raise RuntimeError("close failed")
-
-    monkeypatch.setattr("vllm_omni.entrypoints.omni.Omni", _OwnedOmni)
-    if close_raises:
-        with pytest.raises(RuntimeError, match="close failed"), OmniRunner("fake-model"):
-            pass
-    else:
-        with OmniRunner("fake-model"):
-            pass
-
-    assert owned[0].poll() is not None
-    assert existing.poll() is None
-    assert late_unrelated[0].poll() is None
-
-
-def test_runner_startup_failure_cleans_only_new_workers(
-    monkeypatch: pytest.MonkeyPatch, live_workers: list[subprocess.Popen[bytes]]
-) -> None:
-    unrelated = _start_engine_worker(live_workers)
-    owned: list[subprocess.Popen[bytes]] = []
-    monkeypatch.setattr("tests.helpers.runtime.cleanup_test_environment", lambda: None)
-
-    class _FailingOmni:
-        def __init__(self, *args: object, **kwargs: object) -> None:
-            owned.append(_start_engine_worker(live_workers))
-            raise RuntimeError("startup failed")
-
-    monkeypatch.setattr("vllm_omni.entrypoints.omni.Omni", _FailingOmni)
-    with pytest.raises(RuntimeError, match="startup failed"):
-        OmniRunner("fake-model")
-
-    assert owned[0].poll() is not None
-    assert unrelated.poll() is None
-
-
-def test_runner_cleanup_rejects_stale_process_identity(live_workers: list[subprocess.Popen[bytes]]) -> None:
-    unrelated = _start_engine_worker(live_workers)
-    runner = object.__new__(OmniRunner)
-    runner._owned_engine_processes = {unrelated.pid: psutil.Process(unrelated.pid).create_time() + 1}
-
-    runner._cleanup_process()
-
-    assert unrelated.poll() is None
-
-
-def test_runner_cleanup_kills_owned_worker_ignoring_terminate(
-    monkeypatch: pytest.MonkeyPatch, live_workers: list[subprocess.Popen[bytes]]
-) -> None:
-    owned: list[subprocess.Popen[bytes]] = []
-    monkeypatch.setattr("tests.helpers.runtime.cleanup_test_environment", lambda: None)
-
-    class _StubbornOmni:
-        def __init__(self, *args: object, **kwargs: object) -> None:
-            owned.append(_start_engine_worker(live_workers, ignore_terminate=True))
-
-        def close(self) -> None:
-            pass
-
-    monkeypatch.setattr("vllm_omni.entrypoints.omni.Omni", _StubbornOmni)
-    with OmniRunner("fake-model"):
-        assert owned[0].poll() is None
-
-    assert owned[0].poll() is not None

vllm_omni/engine/__init__.py

@@ -123,6 +123,7 @@ class OmniEngineCoreRequest(EngineCoreRequest):
             trace_headers=request.trace_headers,
             resumable=request.resumable,
             external_req_id=request.external_req_id,
+            session_id=request.session_id,
             reasoning_ended=request.reasoning_ended,
             reasoning_parser_kwargs=request.reasoning_parser_kwargs,
             abort_immediately=request.abort_immediately,