One package that makes the POSIX assumptions measured in W0-W8 hold in
every process vLLM / vLLM-Omni starts, and reports what it did:
- provides fcntl (flock/lockf on msvcrt.locking; LOCK_SH served as
exclusive) and uvloop (asyncio.run on a selector loop) when absent;
- installs WindowsSelectorEventLoopPolicy and a signal.signal fallback
for loop.add_signal_handler on the Windows loop classes;
- replaces whole vLLM's get_open_zmq_ipc_path / find_loaded_library when
the wheel lacks the branch patch and the upstream body hash is known;
- verifies the wheel-only sites (sentinel poll, int64 seed) and reports
wheel_required at the exact site instead of failing downstream;
- shm_dir() replaces the /dev/shm literals; os.geteuid provided.
Activated from vllm_omni/patch.py and as vllm.general_plugins /
vllm_omni.general_plugins entry points (idempotent; no-op off Windows).
prints the audit; the M0 placement
report embeds it. 16 Linux tests through injected primitives.
Design: analysis/design_windows_compat_plugin_20260921.md
Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
uvloop ships no Windows wheels, so 'import uvloop' at module scope in
entrypoints/cli/serve.py killed vllm-omni serve on Windows at import
(measured in the serving e2e after the fcntl fix). _run_forever() uses
uvloop where present and asyncio.run on WindowsSelectorEventLoopPolicy
otherwise, which zmq.asyncio needs. The remaining serve-import blocker
on the Windows venv was a missing dependency, torchaudio (vLLM's own
requirement), installed into the venvs rather than patched.
Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
test_e2e_serve_text.py no longer imports tests.helpers.runtime (it pulls
the media/diffusion test helpers and therefore diffusers, absent from the
Windows venv); a small Popen launcher with a psutil process-tree kill
replaces OmniServer for this one test.
vllm-omni serve died at import on Windows: entrypoints/cli imports
benchmarks.patch -> benchmarks/omniinteract.py, which did 'import fcntl'
at module scope. Its output lock is rebuilt on the fork's
_filelock_compat primitive (fcntl on POSIX, msvcrt on Windows).
engine/stage_phase_lock.py (parallel_stage_init's SH/EX device locks)
gets the same treatment: fcntl optional, modes spelled locally, and on
Windows both modes map to the exclusive byte lock -- more serialising,
never less safe. Measured: the serving e2e's server exited with
ModuleNotFoundError: No module named 'fcntl' on both Windows venvs.
Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>