Le Tue, 22 Oct 2013 10:54:03 +0200, Victor Stinner <victor.stin...@gmail.com> a écrit :
> Hi, > > Would it be possible to use os.pipe() on all OSes except AIX? > > Pipes and socket pairs may have minor differences, but some > applications may rely on these minor differences. For example, is the > buffer size the same? For example, in test.support, we have two > constants: PIPE_MAX_SIZE (4 MB) and SOCK_MAX_SIZE (16 MB). For the record, pipe I/O seems a little faster than socket I/O under Linux: $ ./python -m timeit -s "import os, socket; a,b = socket.socketpair(); r=a.fileno(); w=b.fileno(); x=b'x'*1000" "os.write(w, x); os.read(r, 1000)" 1000000 loops, best of 3: 1.1 usec per loop $ ./python -m timeit -s "import os, socket; a,b = socket.socketpair(); x=b'x'*1000" "a.sendall(x); b.recv(1000)" 1000000 loops, best of 3: 1.02 usec per loop $ ./python -m timeit -s "import os; r, w = os.pipe(); x=b'x'*1000" "os.write(w, x); os.read(r, 1000)" 1000000 loops, best of 3: 0.82 usec per loop Regards Antoine. > > Victor > > 2013/10/22 guido.van.rossum <python-check...@python.org>: > > http://hg.python.org/cpython/rev/2a0bda8d283d > > changeset: 86557:2a0bda8d283d > > user: Guido van Rossum <gu...@dropbox.com> > > date: Mon Oct 21 20:37:14 2013 -0700 > > summary: > > Switch subprocess stdin to a socketpair, attempting to fix issue > > #19293 (AIX hang). > > > > files: > > Lib/asyncio/unix_events.py | 29 +++++++++- > > Lib/test/test_asyncio/test_unix_events.py | 7 ++ > > 2 files changed, 32 insertions(+), 4 deletions(-) > > > > > > diff --git a/Lib/asyncio/unix_events.py b/Lib/asyncio/unix_events.py > > --- a/Lib/asyncio/unix_events.py > > +++ b/Lib/asyncio/unix_events.py > > if stdin == subprocess.PIPE: > > self._pipes[STDIN] = None > > + # Use a socket pair for stdin, since not all platforms > > + # support selecting read events on the write end of a > > + # socket (which we use in order to detect closing of > > the > > + # other end). Notably this is needed on AIX, and works > > + # just fine on other platforms. > > + stdin, stdin_w = self._loop._socketpair() > > if stdout == subprocess.PIPE: > > self._pipes[STDOUT] = None > > if stderr == subprocess.PIPE: _______________________________________________ Python-Dev mailing list Python-Dev@python.org https://mail.python.org/mailman/listinfo/python-dev Unsubscribe: https://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
