162 threadchannel worker parked on recv hangs process shutdown when the sender finishes without close#166
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…es without close()
A worker spawned with Async\spawn_thread() and parked on ThreadChannel::recv()
kept the whole process alive once the owning side finished without close(): the
non-awaited worker pinned the parent scheduler, so the parent never reached
request shutdown to release the channel, and recv() blocked forever with no
output and no diagnostic.
1. Transparent thread completion event (libuv_reactor.c/.h). The event is hidden
and its notify handle is unref'd by default, so a non-awaited worker no longer
keeps the parent loop alive. start() creates the OS thread on the first call
(ASYNC_THREAD_F_LAUNCHED) and stays transparent; a later start() from an
awaiter arms the wait (uv_ref + count). stop() disarms back to transparent.
CLOSED is set on completion in notify_cb after stop(), because the stop
prologue short-circuits on a closed event and would skip the disarm. An
awaited worker is kept alive by its suspended coroutine.
2. Endpoint-drop disconnect for PHP ThreadChannels (thread_channel.c/.h). A
channel left with a single wrapper (ref_count <= 1) has no other thread that
could be a peer, so parked recv()/send() wake with ThreadChannelException
("no producers/consumers remain"), checked both at park (last peer dropped
before we parked) and on dispose (peer drops while parked). Raw pool channels
keep auto_disconnect off and close() explicitly.
Tests: thread_channel/042; full thread/thread_channel/thread_pool suites green.
Claude-Session: https://claude.ai/code/session_01NMdPEuD85qzTjv2N4ihTQU
Codecov Report✅ All modified and coverable lines are covered by tests. 📢 Thoughts on this report? Let us know! |
…el registry Replaces the ref_count-based disconnect from the previous commit, which was wrong for fan-out (N>1 workers on one channel) and the thread pool. ref_count counts wrappers, not endpoints, so no per-channel condition is reliable. Instead: every live shared channel is tracked in a process-wide registry, and libuv_reactor_quiesce() closes them all before waiting for child threads. A worker parked on recv()/send() then wakes with ThreadChannelException and exits. Combined with the transparent thread event (parent reaches shutdown instead of pinning on a non-awaited worker), this fixes the hang for any number of workers. Tests: thread_channel/042 (recv), 043 (producer coroutine), 044 (fan-out). Claude-Session: https://claude.ai/code/session_01NMdPEuD85qzTjv2N4ihTQU
…ent worker) Worker output emitted during shutdown disconnect double-flushed on the CI multi-core runner (a thread-stdout artifact, not a logic double-disconnect; 40x local runs were clean). The tests now keep the worker silent on disconnect and assert only the owner output: a hang fails via timeout, a spurious value fails via extra output. Claude-Session: https://claude.ai/code/session_01NMdPEuD85qzTjv2N4ihTQU
…shutdown thread_channel/orphan_recv.feature: a coroutine spawns N workers parked on recv() of a fresh ThreadChannel and finishes without close()/await(). The shutdown registry close_all() must disconnect every worker. New step in _harness/Steps.php. 5 .phpt x random:1..30 green on ASAN+async-fuzz (150 interleavings, no hang/leak/UAF), including fan-out. Claude-Session: https://claude.ai/code/session_01NMdPEuD85qzTjv2N4ihTQU
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