mirrors/cpython
1
0
Fork 0
mirror of https://github.com/python/cpython.git synced 2025-08-30 21:48:47 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions 7

Issue #12328: Fix multiprocessing's use of overlapped I/O on Windows.

Browse source 
Also, add a multiprocessing.connection.wait(rlist, timeout=None) function
for polling multiple objects at once.  Patch by sbt.

Complete changelist from sbt's patch:

* Adds a wait(rlist, timeout=None) function for polling multiple
  objects at once.  On Unix this is just a wrapper for
  select(rlist, [], [], timeout=None).

* Removes use of the SentinelReady exception and the sentinels argument
  to certain methods.  concurrent.futures.process has been changed to
  use wait() instead of SentinelReady.

* Fixes bugs concerning PipeConnection.poll() and messages of zero
  length.

* Fixes PipeListener.accept() to call ConnectNamedPipe() with
  overlapped=True.

* Fixes Queue.empty() and SimpleQueue.empty() so that they are
  threadsafe on Windows.

* Now PipeConnection.poll() and wait() will not modify the pipe except
  possibly by consuming a zero length message.  (Previously poll()
  could consume a partial message.)

* All of multiprocesing's pipe related blocking functions/methods are
  now interruptible by SIGINT on Windows.
This commit is contained in:
Antoine Pitrou 2012-03-05 19:28:37 +01:00
parent 1e88f3faa6
commit bdb1cf1ca5
7 changed files with 581 additions and 152 deletions
Download patch file Download diff file Expand all files Collapse all files

9
Lib/multiprocessing/queues.py
View file

@ -44,7 +44,7 @@ import errno
from queue import Empty, Full
import _multiprocessing
from multiprocessing.connection import Pipe, SentinelReady
from multiprocessing.connection import Pipe
from multiprocessing.synchronize import Lock, BoundedSemaphore, Semaphore, Condition
from multiprocessing.util import debug, info, Finalize, register_after_fork
from multiprocessing.forking import assert_spawning
@ -360,6 +360,7 @@ class SimpleQueue(object):
def __init__(self):
self._reader, self._writer = Pipe(duplex=False)
self._rlock = Lock()
self._poll = self._reader.poll
if sys.platform == 'win32':
self._wlock = None
else:
@ -367,7 +368,7 @@ class SimpleQueue(object):
self._make_methods()
def empty(self):
return not self._reader.poll()
return not self._poll()
def __getstate__(self):
assert_spawning(self)
@ -380,10 +381,10 @@ class SimpleQueue(object):
def _make_methods(self):
recv = self._reader.recv
racquire, rrelease = self._rlock.acquire, self._rlock.release
def get(*, sentinels=None):
def get():
racquire()
try:
return recv(sentinels)
return recv()
finally:
rrelease()
self.get = get