817 lines
26 KiB
Python
817 lines
26 KiB
Python
#
|
|
# Module providing the `Pool` class for managing a process pool
|
|
#
|
|
# multiprocessing/pool.py
|
|
#
|
|
# Copyright (c) 2006-2008, R Oudkerk
|
|
# Licensed to PSF under a Contributor Agreement.
|
|
#
|
|
|
|
__all__ = ['Pool', 'ThreadPool']
|
|
|
|
#
|
|
# Imports
|
|
#
|
|
|
|
import threading
|
|
import queue
|
|
import itertools
|
|
import collections
|
|
import os
|
|
import time
|
|
import traceback
|
|
|
|
# If threading is available then ThreadPool should be provided. Therefore
|
|
# we avoid top-level imports which are liable to fail on some systems.
|
|
from . import util
|
|
from . import get_context, TimeoutError
|
|
|
|
#
|
|
# Constants representing the state of a pool
|
|
#
|
|
|
|
RUN = 0
|
|
CLOSE = 1
|
|
TERMINATE = 2
|
|
|
|
#
|
|
# Miscellaneous
|
|
#
|
|
|
|
job_counter = itertools.count()
|
|
|
|
def mapstar(args):
|
|
return list(map(*args))
|
|
|
|
def starmapstar(args):
|
|
return list(itertools.starmap(args[0], args[1]))
|
|
|
|
#
|
|
# Hack to embed stringification of remote traceback in local traceback
|
|
#
|
|
|
|
class RemoteTraceback(Exception):
|
|
def __init__(self, tb):
|
|
self.tb = tb
|
|
def __str__(self):
|
|
return self.tb
|
|
|
|
class ExceptionWithTraceback:
|
|
def __init__(self, exc, tb):
|
|
tb = traceback.format_exception(type(exc), exc, tb)
|
|
tb = ''.join(tb)
|
|
self.exc = exc
|
|
self.tb = '\n"""\n%s"""' % tb
|
|
def __reduce__(self):
|
|
return rebuild_exc, (self.exc, self.tb)
|
|
|
|
def rebuild_exc(exc, tb):
|
|
exc.__cause__ = RemoteTraceback(tb)
|
|
return exc
|
|
|
|
#
|
|
# Code run by worker processes
|
|
#
|
|
|
|
class MaybeEncodingError(Exception):
|
|
"""Wraps possible unpickleable errors, so they can be
|
|
safely sent through the socket."""
|
|
|
|
def __init__(self, exc, value):
|
|
self.exc = repr(exc)
|
|
self.value = repr(value)
|
|
super(MaybeEncodingError, self).__init__(self.exc, self.value)
|
|
|
|
def __str__(self):
|
|
return "Error sending result: '%s'. Reason: '%s'" % (self.value,
|
|
self.exc)
|
|
|
|
def __repr__(self):
|
|
return "<%s: %s>" % (self.__class__.__name__, self)
|
|
|
|
|
|
def worker(inqueue, outqueue, initializer=None, initargs=(), maxtasks=None,
|
|
wrap_exception=False):
|
|
if (maxtasks is not None) and not (isinstance(maxtasks, int)
|
|
and maxtasks >= 1):
|
|
raise AssertionError("Maxtasks {!r} is not valid".format(maxtasks))
|
|
put = outqueue.put
|
|
get = inqueue.get
|
|
if hasattr(inqueue, '_writer'):
|
|
inqueue._writer.close()
|
|
outqueue._reader.close()
|
|
|
|
if initializer is not None:
|
|
initializer(*initargs)
|
|
|
|
completed = 0
|
|
while maxtasks is None or (maxtasks and completed < maxtasks):
|
|
try:
|
|
task = get()
|
|
except (EOFError, OSError):
|
|
util.debug('worker got EOFError or OSError -- exiting')
|
|
break
|
|
|
|
if task is None:
|
|
util.debug('worker got sentinel -- exiting')
|
|
break
|
|
|
|
job, i, func, args, kwds = task
|
|
try:
|
|
result = (True, func(*args, **kwds))
|
|
except Exception as e:
|
|
if wrap_exception and func is not _helper_reraises_exception:
|
|
e = ExceptionWithTraceback(e, e.__traceback__)
|
|
result = (False, e)
|
|
try:
|
|
put((job, i, result))
|
|
except Exception as e:
|
|
wrapped = MaybeEncodingError(e, result[1])
|
|
util.debug("Possible encoding error while sending result: %s" % (
|
|
wrapped))
|
|
put((job, i, (False, wrapped)))
|
|
|
|
task = job = result = func = args = kwds = None
|
|
completed += 1
|
|
util.debug('worker exiting after %d tasks' % completed)
|
|
|
|
def _helper_reraises_exception(ex):
|
|
'Pickle-able helper function for use by _guarded_task_generation.'
|
|
raise ex
|
|
|
|
#
|
|
# Class representing a process pool
|
|
#
|
|
|
|
class Pool(object):
|
|
'''
|
|
Class which supports an async version of applying functions to arguments.
|
|
'''
|
|
_wrap_exception = True
|
|
|
|
def Process(self, *args, **kwds):
|
|
return self._ctx.Process(*args, **kwds)
|
|
|
|
def __init__(self, processes=None, initializer=None, initargs=(),
|
|
maxtasksperchild=None, context=None):
|
|
self._ctx = context or get_context()
|
|
self._setup_queues()
|
|
self._taskqueue = queue.Queue()
|
|
self._cache = {}
|
|
self._state = RUN
|
|
self._maxtasksperchild = maxtasksperchild
|
|
self._initializer = initializer
|
|
self._initargs = initargs
|
|
|
|
if processes is None:
|
|
processes = os.cpu_count() or 1
|
|
if processes < 1:
|
|
raise ValueError("Number of processes must be at least 1")
|
|
|
|
if initializer is not None and not callable(initializer):
|
|
raise TypeError('initializer must be a callable')
|
|
|
|
self._processes = processes
|
|
self._pool = []
|
|
self._repopulate_pool()
|
|
|
|
self._worker_handler = threading.Thread(
|
|
target=Pool._handle_workers,
|
|
args=(self, )
|
|
)
|
|
self._worker_handler.daemon = True
|
|
self._worker_handler._state = RUN
|
|
self._worker_handler.start()
|
|
|
|
|
|
self._task_handler = threading.Thread(
|
|
target=Pool._handle_tasks,
|
|
args=(self._taskqueue, self._quick_put, self._outqueue,
|
|
self._pool, self._cache)
|
|
)
|
|
self._task_handler.daemon = True
|
|
self._task_handler._state = RUN
|
|
self._task_handler.start()
|
|
|
|
self._result_handler = threading.Thread(
|
|
target=Pool._handle_results,
|
|
args=(self._outqueue, self._quick_get, self._cache)
|
|
)
|
|
self._result_handler.daemon = True
|
|
self._result_handler._state = RUN
|
|
self._result_handler.start()
|
|
|
|
self._terminate = util.Finalize(
|
|
self, self._terminate_pool,
|
|
args=(self._taskqueue, self._inqueue, self._outqueue, self._pool,
|
|
self._worker_handler, self._task_handler,
|
|
self._result_handler, self._cache),
|
|
exitpriority=15
|
|
)
|
|
|
|
def _join_exited_workers(self):
|
|
"""Cleanup after any worker processes which have exited due to reaching
|
|
their specified lifetime. Returns True if any workers were cleaned up.
|
|
"""
|
|
cleaned = False
|
|
for i in reversed(range(len(self._pool))):
|
|
worker = self._pool[i]
|
|
if worker.exitcode is not None:
|
|
# worker exited
|
|
util.debug('cleaning up worker %d' % i)
|
|
worker.join()
|
|
cleaned = True
|
|
del self._pool[i]
|
|
return cleaned
|
|
|
|
def _repopulate_pool(self):
|
|
"""Bring the number of pool processes up to the specified number,
|
|
for use after reaping workers which have exited.
|
|
"""
|
|
for i in range(self._processes - len(self._pool)):
|
|
w = self.Process(target=worker,
|
|
args=(self._inqueue, self._outqueue,
|
|
self._initializer,
|
|
self._initargs, self._maxtasksperchild,
|
|
self._wrap_exception)
|
|
)
|
|
self._pool.append(w)
|
|
w.name = w.name.replace('Process', 'PoolWorker')
|
|
w.daemon = True
|
|
w.start()
|
|
util.debug('added worker')
|
|
|
|
def _maintain_pool(self):
|
|
"""Clean up any exited workers and start replacements for them.
|
|
"""
|
|
if self._join_exited_workers():
|
|
self._repopulate_pool()
|
|
|
|
def _setup_queues(self):
|
|
self._inqueue = self._ctx.SimpleQueue()
|
|
self._outqueue = self._ctx.SimpleQueue()
|
|
self._quick_put = self._inqueue._writer.send
|
|
self._quick_get = self._outqueue._reader.recv
|
|
|
|
def apply(self, func, args=(), kwds={}):
|
|
'''
|
|
Equivalent of `func(*args, **kwds)`.
|
|
Pool must be running.
|
|
'''
|
|
return self.apply_async(func, args, kwds).get()
|
|
|
|
def map(self, func, iterable, chunksize=None):
|
|
'''
|
|
Apply `func` to each element in `iterable`, collecting the results
|
|
in a list that is returned.
|
|
'''
|
|
return self._map_async(func, iterable, mapstar, chunksize).get()
|
|
|
|
def starmap(self, func, iterable, chunksize=None):
|
|
'''
|
|
Like `map()` method but the elements of the `iterable` are expected to
|
|
be iterables as well and will be unpacked as arguments. Hence
|
|
`func` and (a, b) becomes func(a, b).
|
|
'''
|
|
return self._map_async(func, iterable, starmapstar, chunksize).get()
|
|
|
|
def starmap_async(self, func, iterable, chunksize=None, callback=None,
|
|
error_callback=None):
|
|
'''
|
|
Asynchronous version of `starmap()` method.
|
|
'''
|
|
return self._map_async(func, iterable, starmapstar, chunksize,
|
|
callback, error_callback)
|
|
|
|
def _guarded_task_generation(self, result_job, func, iterable):
|
|
'''Provides a generator of tasks for imap and imap_unordered with
|
|
appropriate handling for iterables which throw exceptions during
|
|
iteration.'''
|
|
try:
|
|
i = -1
|
|
for i, x in enumerate(iterable):
|
|
yield (result_job, i, func, (x,), {})
|
|
except Exception as e:
|
|
yield (result_job, i+1, _helper_reraises_exception, (e,), {})
|
|
|
|
def imap(self, func, iterable, chunksize=1):
|
|
'''
|
|
Equivalent of `map()` -- can be MUCH slower than `Pool.map()`.
|
|
'''
|
|
if self._state != RUN:
|
|
raise ValueError("Pool not running")
|
|
if chunksize == 1:
|
|
result = IMapIterator(self._cache)
|
|
self._taskqueue.put(
|
|
(
|
|
self._guarded_task_generation(result._job, func, iterable),
|
|
result._set_length
|
|
))
|
|
return result
|
|
else:
|
|
if chunksize < 1:
|
|
raise ValueError(
|
|
"Chunksize must be 1+, not {0:n}".format(
|
|
chunksize))
|
|
task_batches = Pool._get_tasks(func, iterable, chunksize)
|
|
result = IMapIterator(self._cache)
|
|
self._taskqueue.put(
|
|
(
|
|
self._guarded_task_generation(result._job,
|
|
mapstar,
|
|
task_batches),
|
|
result._set_length
|
|
))
|
|
return (item for chunk in result for item in chunk)
|
|
|
|
def imap_unordered(self, func, iterable, chunksize=1):
|
|
'''
|
|
Like `imap()` method but ordering of results is arbitrary.
|
|
'''
|
|
if self._state != RUN:
|
|
raise ValueError("Pool not running")
|
|
if chunksize == 1:
|
|
result = IMapUnorderedIterator(self._cache)
|
|
self._taskqueue.put(
|
|
(
|
|
self._guarded_task_generation(result._job, func, iterable),
|
|
result._set_length
|
|
))
|
|
return result
|
|
else:
|
|
if chunksize < 1:
|
|
raise ValueError(
|
|
"Chunksize must be 1+, not {0!r}".format(chunksize))
|
|
task_batches = Pool._get_tasks(func, iterable, chunksize)
|
|
result = IMapUnorderedIterator(self._cache)
|
|
self._taskqueue.put(
|
|
(
|
|
self._guarded_task_generation(result._job,
|
|
mapstar,
|
|
task_batches),
|
|
result._set_length
|
|
))
|
|
return (item for chunk in result for item in chunk)
|
|
|
|
def apply_async(self, func, args=(), kwds={}, callback=None,
|
|
error_callback=None):
|
|
'''
|
|
Asynchronous version of `apply()` method.
|
|
'''
|
|
if self._state != RUN:
|
|
raise ValueError("Pool not running")
|
|
result = ApplyResult(self._cache, callback, error_callback)
|
|
self._taskqueue.put(([(result._job, 0, func, args, kwds)], None))
|
|
return result
|
|
|
|
def map_async(self, func, iterable, chunksize=None, callback=None,
|
|
error_callback=None):
|
|
'''
|
|
Asynchronous version of `map()` method.
|
|
'''
|
|
return self._map_async(func, iterable, mapstar, chunksize, callback,
|
|
error_callback)
|
|
|
|
def _map_async(self, func, iterable, mapper, chunksize=None, callback=None,
|
|
error_callback=None):
|
|
'''
|
|
Helper function to implement map, starmap and their async counterparts.
|
|
'''
|
|
if self._state != RUN:
|
|
raise ValueError("Pool not running")
|
|
if not hasattr(iterable, '__len__'):
|
|
iterable = list(iterable)
|
|
|
|
if chunksize is None:
|
|
chunksize, extra = divmod(len(iterable), len(self._pool) * 4)
|
|
if extra:
|
|
chunksize += 1
|
|
if len(iterable) == 0:
|
|
chunksize = 0
|
|
|
|
task_batches = Pool._get_tasks(func, iterable, chunksize)
|
|
result = MapResult(self._cache, chunksize, len(iterable), callback,
|
|
error_callback=error_callback)
|
|
self._taskqueue.put(
|
|
(
|
|
self._guarded_task_generation(result._job,
|
|
mapper,
|
|
task_batches),
|
|
None
|
|
)
|
|
)
|
|
return result
|
|
|
|
@staticmethod
|
|
def _handle_workers(pool):
|
|
thread = threading.current_thread()
|
|
|
|
# Keep maintaining workers until the cache gets drained, unless the pool
|
|
# is terminated.
|
|
while thread._state == RUN or (pool._cache and thread._state != TERMINATE):
|
|
pool._maintain_pool()
|
|
time.sleep(0.1)
|
|
# send sentinel to stop workers
|
|
pool._taskqueue.put(None)
|
|
util.debug('worker handler exiting')
|
|
|
|
@staticmethod
|
|
def _handle_tasks(taskqueue, put, outqueue, pool, cache):
|
|
thread = threading.current_thread()
|
|
|
|
for taskseq, set_length in iter(taskqueue.get, None):
|
|
task = None
|
|
try:
|
|
# iterating taskseq cannot fail
|
|
for task in taskseq:
|
|
if thread._state:
|
|
util.debug('task handler found thread._state != RUN')
|
|
break
|
|
try:
|
|
put(task)
|
|
except Exception as e:
|
|
job, idx = task[:2]
|
|
try:
|
|
cache[job]._set(idx, (False, e))
|
|
except KeyError:
|
|
pass
|
|
else:
|
|
if set_length:
|
|
util.debug('doing set_length()')
|
|
idx = task[1] if task else -1
|
|
set_length(idx + 1)
|
|
continue
|
|
break
|
|
finally:
|
|
task = taskseq = job = None
|
|
else:
|
|
util.debug('task handler got sentinel')
|
|
|
|
try:
|
|
# tell result handler to finish when cache is empty
|
|
util.debug('task handler sending sentinel to result handler')
|
|
outqueue.put(None)
|
|
|
|
# tell workers there is no more work
|
|
util.debug('task handler sending sentinel to workers')
|
|
for p in pool:
|
|
put(None)
|
|
except OSError:
|
|
util.debug('task handler got OSError when sending sentinels')
|
|
|
|
util.debug('task handler exiting')
|
|
|
|
@staticmethod
|
|
def _handle_results(outqueue, get, cache):
|
|
thread = threading.current_thread()
|
|
|
|
while 1:
|
|
try:
|
|
task = get()
|
|
except (OSError, EOFError):
|
|
util.debug('result handler got EOFError/OSError -- exiting')
|
|
return
|
|
|
|
if thread._state:
|
|
assert thread._state == TERMINATE, "Thread not in TERMINATE"
|
|
util.debug('result handler found thread._state=TERMINATE')
|
|
break
|
|
|
|
if task is None:
|
|
util.debug('result handler got sentinel')
|
|
break
|
|
|
|
job, i, obj = task
|
|
try:
|
|
cache[job]._set(i, obj)
|
|
except KeyError:
|
|
pass
|
|
task = job = obj = None
|
|
|
|
while cache and thread._state != TERMINATE:
|
|
try:
|
|
task = get()
|
|
except (OSError, EOFError):
|
|
util.debug('result handler got EOFError/OSError -- exiting')
|
|
return
|
|
|
|
if task is None:
|
|
util.debug('result handler ignoring extra sentinel')
|
|
continue
|
|
job, i, obj = task
|
|
try:
|
|
cache[job]._set(i, obj)
|
|
except KeyError:
|
|
pass
|
|
task = job = obj = None
|
|
|
|
if hasattr(outqueue, '_reader'):
|
|
util.debug('ensuring that outqueue is not full')
|
|
# If we don't make room available in outqueue then
|
|
# attempts to add the sentinel (None) to outqueue may
|
|
# block. There is guaranteed to be no more than 2 sentinels.
|
|
try:
|
|
for i in range(10):
|
|
if not outqueue._reader.poll():
|
|
break
|
|
get()
|
|
except (OSError, EOFError):
|
|
pass
|
|
|
|
util.debug('result handler exiting: len(cache)=%s, thread._state=%s',
|
|
len(cache), thread._state)
|
|
|
|
@staticmethod
|
|
def _get_tasks(func, it, size):
|
|
it = iter(it)
|
|
while 1:
|
|
x = tuple(itertools.islice(it, size))
|
|
if not x:
|
|
return
|
|
yield (func, x)
|
|
|
|
def __reduce__(self):
|
|
raise NotImplementedError(
|
|
'pool objects cannot be passed between processes or pickled'
|
|
)
|
|
|
|
def close(self):
|
|
util.debug('closing pool')
|
|
if self._state == RUN:
|
|
self._state = CLOSE
|
|
self._worker_handler._state = CLOSE
|
|
|
|
def terminate(self):
|
|
util.debug('terminating pool')
|
|
self._state = TERMINATE
|
|
self._worker_handler._state = TERMINATE
|
|
self._terminate()
|
|
|
|
def join(self):
|
|
util.debug('joining pool')
|
|
if self._state == RUN:
|
|
raise ValueError("Pool is still running")
|
|
elif self._state not in (CLOSE, TERMINATE):
|
|
raise ValueError("In unknown state")
|
|
self._worker_handler.join()
|
|
self._task_handler.join()
|
|
self._result_handler.join()
|
|
for p in self._pool:
|
|
p.join()
|
|
|
|
@staticmethod
|
|
def _help_stuff_finish(inqueue, task_handler, size):
|
|
# task_handler may be blocked trying to put items on inqueue
|
|
util.debug('removing tasks from inqueue until task handler finished')
|
|
inqueue._rlock.acquire()
|
|
while task_handler.is_alive() and inqueue._reader.poll():
|
|
inqueue._reader.recv()
|
|
time.sleep(0)
|
|
|
|
@classmethod
|
|
def _terminate_pool(cls, taskqueue, inqueue, outqueue, pool,
|
|
worker_handler, task_handler, result_handler, cache):
|
|
# this is guaranteed to only be called once
|
|
util.debug('finalizing pool')
|
|
|
|
worker_handler._state = TERMINATE
|
|
task_handler._state = TERMINATE
|
|
|
|
util.debug('helping task handler/workers to finish')
|
|
cls._help_stuff_finish(inqueue, task_handler, len(pool))
|
|
|
|
if (not result_handler.is_alive()) and (len(cache) != 0):
|
|
raise AssertionError(
|
|
"Cannot have cache with result_hander not alive")
|
|
|
|
result_handler._state = TERMINATE
|
|
outqueue.put(None) # sentinel
|
|
|
|
# We must wait for the worker handler to exit before terminating
|
|
# workers because we don't want workers to be restarted behind our back.
|
|
util.debug('joining worker handler')
|
|
if threading.current_thread() is not worker_handler:
|
|
worker_handler.join()
|
|
|
|
# Terminate workers which haven't already finished.
|
|
if pool and hasattr(pool[0], 'terminate'):
|
|
util.debug('terminating workers')
|
|
for p in pool:
|
|
if p.exitcode is None:
|
|
p.terminate()
|
|
|
|
util.debug('joining task handler')
|
|
if threading.current_thread() is not task_handler:
|
|
task_handler.join()
|
|
|
|
util.debug('joining result handler')
|
|
if threading.current_thread() is not result_handler:
|
|
result_handler.join()
|
|
|
|
if pool and hasattr(pool[0], 'terminate'):
|
|
util.debug('joining pool workers')
|
|
for p in pool:
|
|
if p.is_alive():
|
|
# worker has not yet exited
|
|
util.debug('cleaning up worker %d' % p.pid)
|
|
p.join()
|
|
|
|
def __enter__(self):
|
|
return self
|
|
|
|
def __exit__(self, exc_type, exc_val, exc_tb):
|
|
self.terminate()
|
|
|
|
#
|
|
# Class whose instances are returned by `Pool.apply_async()`
|
|
#
|
|
|
|
class ApplyResult(object):
|
|
|
|
def __init__(self, cache, callback, error_callback):
|
|
self._event = threading.Event()
|
|
self._job = next(job_counter)
|
|
self._cache = cache
|
|
self._callback = callback
|
|
self._error_callback = error_callback
|
|
cache[self._job] = self
|
|
|
|
def ready(self):
|
|
return self._event.is_set()
|
|
|
|
def successful(self):
|
|
if not self.ready():
|
|
raise ValueError("{0!r} not ready".format(self))
|
|
return self._success
|
|
|
|
def wait(self, timeout=None):
|
|
self._event.wait(timeout)
|
|
|
|
def get(self, timeout=None):
|
|
self.wait(timeout)
|
|
if not self.ready():
|
|
raise TimeoutError
|
|
if self._success:
|
|
return self._value
|
|
else:
|
|
raise self._value
|
|
|
|
def _set(self, i, obj):
|
|
self._success, self._value = obj
|
|
if self._callback and self._success:
|
|
self._callback(self._value)
|
|
if self._error_callback and not self._success:
|
|
self._error_callback(self._value)
|
|
self._event.set()
|
|
del self._cache[self._job]
|
|
|
|
AsyncResult = ApplyResult # create alias -- see #17805
|
|
|
|
#
|
|
# Class whose instances are returned by `Pool.map_async()`
|
|
#
|
|
|
|
class MapResult(ApplyResult):
|
|
|
|
def __init__(self, cache, chunksize, length, callback, error_callback):
|
|
ApplyResult.__init__(self, cache, callback,
|
|
error_callback=error_callback)
|
|
self._success = True
|
|
self._value = [None] * length
|
|
self._chunksize = chunksize
|
|
if chunksize <= 0:
|
|
self._number_left = 0
|
|
self._event.set()
|
|
del cache[self._job]
|
|
else:
|
|
self._number_left = length//chunksize + bool(length % chunksize)
|
|
|
|
def _set(self, i, success_result):
|
|
self._number_left -= 1
|
|
success, result = success_result
|
|
if success and self._success:
|
|
self._value[i*self._chunksize:(i+1)*self._chunksize] = result
|
|
if self._number_left == 0:
|
|
if self._callback:
|
|
self._callback(self._value)
|
|
del self._cache[self._job]
|
|
self._event.set()
|
|
else:
|
|
if not success and self._success:
|
|
# only store first exception
|
|
self._success = False
|
|
self._value = result
|
|
if self._number_left == 0:
|
|
# only consider the result ready once all jobs are done
|
|
if self._error_callback:
|
|
self._error_callback(self._value)
|
|
del self._cache[self._job]
|
|
self._event.set()
|
|
|
|
#
|
|
# Class whose instances are returned by `Pool.imap()`
|
|
#
|
|
|
|
class IMapIterator(object):
|
|
|
|
def __init__(self, cache):
|
|
self._cond = threading.Condition(threading.Lock())
|
|
self._job = next(job_counter)
|
|
self._cache = cache
|
|
self._items = collections.deque()
|
|
self._index = 0
|
|
self._length = None
|
|
self._unsorted = {}
|
|
cache[self._job] = self
|
|
|
|
def __iter__(self):
|
|
return self
|
|
|
|
def next(self, timeout=None):
|
|
with self._cond:
|
|
try:
|
|
item = self._items.popleft()
|
|
except IndexError:
|
|
if self._index == self._length:
|
|
raise StopIteration from None
|
|
self._cond.wait(timeout)
|
|
try:
|
|
item = self._items.popleft()
|
|
except IndexError:
|
|
if self._index == self._length:
|
|
raise StopIteration from None
|
|
raise TimeoutError from None
|
|
|
|
success, value = item
|
|
if success:
|
|
return value
|
|
raise value
|
|
|
|
__next__ = next # XXX
|
|
|
|
def _set(self, i, obj):
|
|
with self._cond:
|
|
if self._index == i:
|
|
self._items.append(obj)
|
|
self._index += 1
|
|
while self._index in self._unsorted:
|
|
obj = self._unsorted.pop(self._index)
|
|
self._items.append(obj)
|
|
self._index += 1
|
|
self._cond.notify()
|
|
else:
|
|
self._unsorted[i] = obj
|
|
|
|
if self._index == self._length:
|
|
del self._cache[self._job]
|
|
|
|
def _set_length(self, length):
|
|
with self._cond:
|
|
self._length = length
|
|
if self._index == self._length:
|
|
self._cond.notify()
|
|
del self._cache[self._job]
|
|
|
|
#
|
|
# Class whose instances are returned by `Pool.imap_unordered()`
|
|
#
|
|
|
|
class IMapUnorderedIterator(IMapIterator):
|
|
|
|
def _set(self, i, obj):
|
|
with self._cond:
|
|
self._items.append(obj)
|
|
self._index += 1
|
|
self._cond.notify()
|
|
if self._index == self._length:
|
|
del self._cache[self._job]
|
|
|
|
#
|
|
#
|
|
#
|
|
|
|
class ThreadPool(Pool):
|
|
_wrap_exception = False
|
|
|
|
@staticmethod
|
|
def Process(*args, **kwds):
|
|
from .dummy import Process
|
|
return Process(*args, **kwds)
|
|
|
|
def __init__(self, processes=None, initializer=None, initargs=()):
|
|
Pool.__init__(self, processes, initializer, initargs)
|
|
|
|
def _setup_queues(self):
|
|
self._inqueue = queue.Queue()
|
|
self._outqueue = queue.Queue()
|
|
self._quick_put = self._inqueue.put
|
|
self._quick_get = self._outqueue.get
|
|
|
|
@staticmethod
|
|
def _help_stuff_finish(inqueue, task_handler, size):
|
|
# put sentinels at head of inqueue to make workers finish
|
|
with inqueue.not_empty:
|
|
inqueue.queue.clear()
|
|
inqueue.queue.extend([None] * size)
|
|
inqueue.not_empty.notify_all()
|