New submission from Charles-François Natali: asyncio makes heavy use of SIGCHLD for subprocesses. A consequence of this if that a lot of syscalls can fail with EINTR (see e.g. issue #18885).
The attached patch uses SA_RESTART (through signal.siginterrupt()) to limit EINTR occurrences, e.g. : """ $ ./python -c "import os; from signal import *; signal(SIGALRM, lambda *args: None); alarm(1); os.read(0, 1)" Traceback (most recent call last): File "<string>", line 1, in <module> InterruptedError: [Errno 4] Interrupted system call """ With siginterrupt(False): """ $ ./python -c "import os; from signal import *; signal(SIGALRM, lambda *args: None); siginterrupt(SIGALRM, False); alarm(1); os.read(0, 1)" [manual interruption] ^CTraceback (most recent call last): File "<string>", line 1, in <module> KeyboardInterrupt """ It doesn't come with test because it's hard to come up with a syscall that's guaranteed to be restarted on al OS (and also because I'm having a hard time with all those mock-based asyncio tests ;-), but at least it doesn't break the test suite :-) See https://groups.google.com/d/topic/python-tulip/9T2_tGWe0Sc/discussion for more background. ---------- components: Library (Lib) files: asyncio_sa_restart.diff keywords: patch messages: 204915 nosy: gvanrossum, neologix priority: normal severity: normal stage: patch review status: open title: asyncio: limit EINTR occurrences with SA_RESTART type: enhancement versions: Python 3.4 Added file: http://bugs.python.org/file32923/asyncio_sa_restart.diff _______________________________________ Python tracker <rep...@bugs.python.org> <http://bugs.python.org/issue19850> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
