Add worker loops: run and drive an ErlangEventLoop inside a context - #71
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py_context:start_loop/stop_loop/loop_ref/submit/submit_await and the erlang.server helper let Erlang run N owngil workers that serve TCP/UDP on a socket Erlang bound (py:dup_fd per worker) or adopt accepted fds, and inject coroutines into the running loop. Fixes behind it: owngil contexts had no ErlangEventLoop and returned the main loop from context_get_event_loop; owngil dispatch was blocking on a dirty scheduler with a 30 s cap; transports closed fds still in the poll set (erts_poll reports under churn); READ re-arm from the loop thread crashed in enif_select; task start failures were dropped. Includes CT suite, Python unit tests, gated stress suite, bench script and docs/workers.md.
…ng loop Tasks beyond MAX_TASK_BATCH queued before the worker ran were stranded: submit_task sends no new wakeup while one is pending and the running-loop branch returned ok. Seen as test_submit_ordering timeouts on slow CI.
The io queue can store several small task binaries in one iovec element; dequeuing iov_len per task dropped every task after the first in that element (every second submit lost on slow CI runners).
A loop running on its own thread consumes pending events itself; sending task_ready for every timer or fd event made the worker attach to the subinterpreter and take its GIL for nothing. Track that state in the loop struct (_set_running_for) and only wake the loop thread.
asyncio cancels a handle after it ran (sleep's finally); a recycled handle then cancels the callback that reused it. Only _dispatch fd handles are pooled now. Explains the every-second-task loss on CI.
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Runtime API for gunicorn-style Python workers inside the VM (the arbiter itself will live in hornbeam).
Added
py_context:start_loop/1,2,stop_loop/1,2,loop_ref/1,submit/4,5,submit_await/4,5,6;{py_loop_exit, Ctx, Result}to the owner;{error, loop_running}for call/eval/exec while a loop runs;preloadoption onpy_context:new/1.erlang.server:serve(listen_fd, factory, udp=False),adopt(fd, factory),stop_serving.process_ready_tasksattaches to the subinterpreter), wake on inject, task start failures reported to the caller.Fixed
ErlangEventLoop;context_get_event_loopreturned the main loop and re-pointed its worker.erts_poll/ stealing control reports); READ re-arm from the loop thread crashed inenif_select.Tests:
py_worker_loop_SUITE(22 cases), Python unit tests (test_server,test_transport_close,test_loop_helpers),py_worker_loop_stress_SUITE(STRESS=1). Bench:examples/bench_worker_loop.erl. Docs:docs/workers.md.Full CT on Python 3.14: 619 passed, 14 expected skips. Python 3.12: owngil group skips, rest passes.