Revert the switch to futures for now
Without it, we get random hangs on parse failure. With it, some folks have seen hangs even on successful cases. The former is clearly less problematic. This is temporary, until I can finish investigating the root causes of both issues. (Bitbake rev: db689a99beffea1a285cdfc74a58fe73f1666987) Signed-off-by: Christopher Larson <kergoth@gmail.com> Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
This commit is contained in:
Christopher Larson
Richard Purdie
parent
d366c1890e
commit
754847f34b
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@ -32,7 +32,6 @@ import sre_constants
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import threading
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from cStringIO import StringIO
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from contextlib import closing
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from concurrent import futures
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from functools import wraps
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from collections import defaultdict
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import bb, bb.exceptions, bb.command
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@ -1453,16 +1452,20 @@ class CookerParser(object):
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self.start()
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def start(self):
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def init(cfg):
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parse_file.cfg = cfg
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multiprocessing.util.Finalize(None, bb.codeparser.parser_cache_save, args=(self.cooker.configuration.data, ), exitpriority=1)
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self.results = self.load_cached()
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if self.toparse:
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bb.event.fire(bb.event.ParseStarted(self.toparse), self.cfgdata)
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parse_file.cfg = self.cfgdata
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multiprocessing.util.Finalize(None, bb.codeparser.parser_cache_save, args=(self.cfgdata,), exitpriority=1)
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self.executor = futures.ProcessPoolExecutor(max_workers=self.num_processes)
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self.futures = dict((self.executor.submit(parse_file, task), task) for task in self.willparse)
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self.results = itertools.chain(self.results, self.parse_gen())
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self.pool = multiprocessing.Pool(self.num_processes, init, [self.cfgdata])
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parsed = self.pool.imap(parse_file, self.willparse)
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self.pool.close()
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self.results = itertools.chain(self.results, parsed)
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def shutdown(self, clean=True):
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if not self.toparse:
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@ -1475,9 +1478,8 @@ class CookerParser(object):
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self.total)
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bb.event.fire(event, self.cfgdata)
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else:
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for future in self.futures:
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future.cancel()
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self.executor.shutdown()
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self.pool.terminate()
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self.pool.join()
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sync = threading.Thread(target=self.bb_cache.sync)
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sync.start()
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@ -1489,15 +1491,6 @@ class CookerParser(object):
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cached, infos = self.bb_cache.load(filename, appends, self.cfgdata)
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yield not cached, infos
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def parse_gen(self):
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for future in futures.as_completed(self.futures):
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task = self.futures[future]
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exc = future.exception()
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if exc:
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raise exc
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else:
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yield future.result()
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def parse_next(self):
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try:
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parsed, result = self.results.next()
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@ -1,3 +0,0 @@
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from pkgutil import extend_path
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__path__ = extend_path(__path__, __name__)
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@ -1,18 +0,0 @@
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# Copyright 2009 Brian Quinlan. All Rights Reserved.
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# Licensed to PSF under a Contributor Agreement.
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"""Execute computations asynchronously using threads or processes."""
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__author__ = 'Brian Quinlan (brian@sweetapp.com)'
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from concurrent.futures._base import (FIRST_COMPLETED,
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FIRST_EXCEPTION,
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ALL_COMPLETED,
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CancelledError,
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TimeoutError,
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Future,
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Executor,
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wait,
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as_completed)
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from concurrent.futures.process import ProcessPoolExecutor
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from concurrent.futures.thread import ThreadPoolExecutor
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@ -1,575 +0,0 @@
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# Copyright 2009 Brian Quinlan. All Rights Reserved.
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# Licensed to PSF under a Contributor Agreement.
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from __future__ import with_statement
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import functools
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import logging
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import threading
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import time
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try:
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from collections import namedtuple
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except ImportError:
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from concurrent.futures._compat import namedtuple
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__author__ = 'Brian Quinlan (brian@sweetapp.com)'
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FIRST_COMPLETED = 'FIRST_COMPLETED'
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FIRST_EXCEPTION = 'FIRST_EXCEPTION'
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ALL_COMPLETED = 'ALL_COMPLETED'
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_AS_COMPLETED = '_AS_COMPLETED'
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# Possible future states (for internal use by the futures package).
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PENDING = 'PENDING'
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RUNNING = 'RUNNING'
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# The future was cancelled by the user...
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CANCELLED = 'CANCELLED'
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# ...and _Waiter.add_cancelled() was called by a worker.
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CANCELLED_AND_NOTIFIED = 'CANCELLED_AND_NOTIFIED'
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FINISHED = 'FINISHED'
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_FUTURE_STATES = [
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PENDING,
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RUNNING,
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CANCELLED,
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CANCELLED_AND_NOTIFIED,
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FINISHED
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]
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_STATE_TO_DESCRIPTION_MAP = {
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PENDING: "pending",
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RUNNING: "running",
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CANCELLED: "cancelled",
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CANCELLED_AND_NOTIFIED: "cancelled",
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FINISHED: "finished"
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}
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# Logger for internal use by the futures package.
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LOGGER = logging.getLogger("concurrent.futures")
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STDERR_HANDLER = logging.StreamHandler()
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LOGGER.addHandler(STDERR_HANDLER)
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class Error(Exception):
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"""Base class for all future-related exceptions."""
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pass
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class CancelledError(Error):
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"""The Future was cancelled."""
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pass
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class TimeoutError(Error):
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"""The operation exceeded the given deadline."""
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pass
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class _Waiter(object):
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"""Provides the event that wait() and as_completed() block on."""
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def __init__(self):
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self.event = threading.Event()
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self.finished_futures = []
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def add_result(self, future):
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self.finished_futures.append(future)
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def add_exception(self, future):
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self.finished_futures.append(future)
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def add_cancelled(self, future):
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self.finished_futures.append(future)
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class _AsCompletedWaiter(_Waiter):
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"""Used by as_completed()."""
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def __init__(self):
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super(_AsCompletedWaiter, self).__init__()
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self.lock = threading.Lock()
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def add_result(self, future):
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with self.lock:
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super(_AsCompletedWaiter, self).add_result(future)
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self.event.set()
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def add_exception(self, future):
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with self.lock:
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super(_AsCompletedWaiter, self).add_exception(future)
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self.event.set()
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def add_cancelled(self, future):
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with self.lock:
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super(_AsCompletedWaiter, self).add_cancelled(future)
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self.event.set()
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class _FirstCompletedWaiter(_Waiter):
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"""Used by wait(return_when=FIRST_COMPLETED)."""
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def add_result(self, future):
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super(_FirstCompletedWaiter, self).add_result(future)
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self.event.set()
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def add_exception(self, future):
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super(_FirstCompletedWaiter, self).add_exception(future)
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self.event.set()
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def add_cancelled(self, future):
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super(_FirstCompletedWaiter, self).add_cancelled(future)
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self.event.set()
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class _AllCompletedWaiter(_Waiter):
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"""Used by wait(return_when=FIRST_EXCEPTION and ALL_COMPLETED)."""
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def __init__(self, num_pending_calls, stop_on_exception):
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self.num_pending_calls = num_pending_calls
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self.stop_on_exception = stop_on_exception
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super(_AllCompletedWaiter, self).__init__()
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def _decrement_pending_calls(self):
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self.num_pending_calls -= 1
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if not self.num_pending_calls:
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self.event.set()
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def add_result(self, future):
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super(_AllCompletedWaiter, self).add_result(future)
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self._decrement_pending_calls()
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def add_exception(self, future):
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super(_AllCompletedWaiter, self).add_exception(future)
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if self.stop_on_exception:
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self.event.set()
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else:
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self._decrement_pending_calls()
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def add_cancelled(self, future):
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super(_AllCompletedWaiter, self).add_cancelled(future)
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self._decrement_pending_calls()
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class _AcquireFutures(object):
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"""A context manager that does an ordered acquire of Future conditions."""
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def __init__(self, futures):
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self.futures = sorted(futures, key=id)
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def __enter__(self):
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for future in self.futures:
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future._condition.acquire()
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def __exit__(self, *args):
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for future in self.futures:
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future._condition.release()
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def _create_and_install_waiters(fs, return_when):
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if return_when == _AS_COMPLETED:
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waiter = _AsCompletedWaiter()
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elif return_when == FIRST_COMPLETED:
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waiter = _FirstCompletedWaiter()
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else:
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pending_count = sum(
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f._state not in [CANCELLED_AND_NOTIFIED, FINISHED] for f in fs)
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if return_when == FIRST_EXCEPTION:
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waiter = _AllCompletedWaiter(pending_count, stop_on_exception=True)
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elif return_when == ALL_COMPLETED:
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waiter = _AllCompletedWaiter(pending_count, stop_on_exception=False)
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else:
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raise ValueError("Invalid return condition: %r" % return_when)
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for f in fs:
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f._waiters.append(waiter)
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return waiter
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def as_completed(fs, timeout=None):
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"""An iterator over the given futures that yields each as it completes.
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Args:
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fs: The sequence of Futures (possibly created by different Executors) to
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iterate over.
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timeout: The maximum number of seconds to wait. If None, then there
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is no limit on the wait time.
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Returns:
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An iterator that yields the given Futures as they complete (finished or
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cancelled).
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Raises:
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TimeoutError: If the entire result iterator could not be generated
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before the given timeout.
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"""
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if timeout is not None:
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end_time = timeout + time.time()
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with _AcquireFutures(fs):
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finished = set(
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f for f in fs
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if f._state in [CANCELLED_AND_NOTIFIED, FINISHED])
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pending = set(fs) - finished
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waiter = _create_and_install_waiters(fs, _AS_COMPLETED)
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try:
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for future in finished:
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yield future
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while pending:
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if timeout is None:
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wait_timeout = None
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else:
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wait_timeout = end_time - time.time()
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if wait_timeout < 0:
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raise TimeoutError(
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'%d (of %d) futures unfinished' % (
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len(pending), len(fs)))
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waiter.event.wait(wait_timeout)
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with waiter.lock:
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finished = waiter.finished_futures
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waiter.finished_futures = []
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waiter.event.clear()
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for future in finished:
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yield future
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pending.remove(future)
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finally:
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for f in fs:
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f._waiters.remove(waiter)
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DoneAndNotDoneFutures = namedtuple(
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'DoneAndNotDoneFutures', 'done not_done')
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def wait(fs, timeout=None, return_when=ALL_COMPLETED):
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"""Wait for the futures in the given sequence to complete.
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Args:
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fs: The sequence of Futures (possibly created by different Executors) to
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wait upon.
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timeout: The maximum number of seconds to wait. If None, then there
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is no limit on the wait time.
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return_when: Indicates when this function should return. The options
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are:
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FIRST_COMPLETED - Return when any future finishes or is
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cancelled.
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FIRST_EXCEPTION - Return when any future finishes by raising an
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exception. If no future raises an exception
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then it is equivalent to ALL_COMPLETED.
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ALL_COMPLETED - Return when all futures finish or are cancelled.
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Returns:
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A named 2-tuple of sets. The first set, named 'done', contains the
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futures that completed (is finished or cancelled) before the wait
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completed. The second set, named 'not_done', contains uncompleted
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futures.
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"""
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with _AcquireFutures(fs):
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done = set(f for f in fs
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if f._state in [CANCELLED_AND_NOTIFIED, FINISHED])
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not_done = set(fs) - done
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if (return_when == FIRST_COMPLETED) and done:
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return DoneAndNotDoneFutures(done, not_done)
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elif (return_when == FIRST_EXCEPTION) and done:
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if any(f for f in done
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if not f.cancelled() and f.exception() is not None):
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return DoneAndNotDoneFutures(done, not_done)
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if len(done) == len(fs):
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return DoneAndNotDoneFutures(done, not_done)
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waiter = _create_and_install_waiters(fs, return_when)
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waiter.event.wait(timeout)
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for f in fs:
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f._waiters.remove(waiter)
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done.update(waiter.finished_futures)
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return DoneAndNotDoneFutures(done, set(fs) - done)
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class Future(object):
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"""Represents the result of an asynchronous computation."""
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def __init__(self):
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"""Initializes the future. Should not be called by clients."""
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self._condition = threading.Condition()
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self._state = PENDING
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self._result = None
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self._exception = None
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self._waiters = []
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self._done_callbacks = []
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def _invoke_callbacks(self):
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for callback in self._done_callbacks:
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try:
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callback(self)
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except Exception:
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LOGGER.exception('exception calling callback for %r', self)
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def __repr__(self):
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with self._condition:
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if self._state == FINISHED:
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if self._exception:
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return '<Future at %s state=%s raised %s>' % (
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hex(id(self)),
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_STATE_TO_DESCRIPTION_MAP[self._state],
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self._exception.__class__.__name__)
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else:
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return '<Future at %s state=%s returned %s>' % (
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hex(id(self)),
|
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_STATE_TO_DESCRIPTION_MAP[self._state],
|
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self._result.__class__.__name__)
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return '<Future at %s state=%s>' % (
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hex(id(self)),
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_STATE_TO_DESCRIPTION_MAP[self._state])
|
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|
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def cancel(self):
|
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"""Cancel the future if possible.
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|
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Returns True if the future was cancelled, False otherwise. A future
|
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cannot be cancelled if it is running or has already completed.
|
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"""
|
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with self._condition:
|
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if self._state in [RUNNING, FINISHED]:
|
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return False
|
||||
|
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if self._state in [CANCELLED, CANCELLED_AND_NOTIFIED]:
|
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return True
|
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|
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self._state = CANCELLED
|
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self._condition.notify_all()
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|
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self._invoke_callbacks()
|
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return True
|
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|
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def cancelled(self):
|
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"""Return True if the future has cancelled."""
|
||||
with self._condition:
|
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return self._state in [CANCELLED, CANCELLED_AND_NOTIFIED]
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|
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def running(self):
|
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"""Return True if the future is currently executing."""
|
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with self._condition:
|
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return self._state == RUNNING
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|
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def done(self):
|
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"""Return True of the future was cancelled or finished executing."""
|
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with self._condition:
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return self._state in [CANCELLED, CANCELLED_AND_NOTIFIED, FINISHED]
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|
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def __get_result(self):
|
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if self._exception:
|
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raise self._exception
|
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else:
|
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return self._result
|
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|
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def add_done_callback(self, fn):
|
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"""Attaches a callable that will be called when the future finishes.
|
||||
|
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Args:
|
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fn: A callable that will be called with this future as its only
|
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argument when the future completes or is cancelled. The callable
|
||||
will always be called by a thread in the same process in which
|
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it was added. If the future has already completed or been
|
||||
cancelled then the callable will be called immediately. These
|
||||
callables are called in the order that they were added.
|
||||
"""
|
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with self._condition:
|
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if self._state not in [CANCELLED, CANCELLED_AND_NOTIFIED, FINISHED]:
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self._done_callbacks.append(fn)
|
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return
|
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fn(self)
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|
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def result(self, timeout=None):
|
||||
"""Return the result of the call that the future represents.
|
||||
|
||||
Args:
|
||||
timeout: The number of seconds to wait for the result if the future
|
||||
isn't done. If None, then there is no limit on the wait time.
|
||||
|
||||
Returns:
|
||||
The result of the call that the future represents.
|
||||
|
||||
Raises:
|
||||
CancelledError: If the future was cancelled.
|
||||
TimeoutError: If the future didn't finish executing before the given
|
||||
timeout.
|
||||
Exception: If the call raised then that exception will be raised.
|
||||
"""
|
||||
with self._condition:
|
||||
if self._state in [CANCELLED, CANCELLED_AND_NOTIFIED]:
|
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raise CancelledError()
|
||||
elif self._state == FINISHED:
|
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return self.__get_result()
|
||||
|
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self._condition.wait(timeout)
|
||||
|
||||
if self._state in [CANCELLED, CANCELLED_AND_NOTIFIED]:
|
||||
raise CancelledError()
|
||||
elif self._state == FINISHED:
|
||||
return self.__get_result()
|
||||
else:
|
||||
raise TimeoutError()
|
||||
|
||||
def exception(self, timeout=None):
|
||||
"""Return the exception raised by the call that the future represents.
|
||||
|
||||
Args:
|
||||
timeout: The number of seconds to wait for the exception if the
|
||||
future isn't done. If None, then there is no limit on the wait
|
||||
time.
|
||||
|
||||
Returns:
|
||||
The exception raised by the call that the future represents or None
|
||||
if the call completed without raising.
|
||||
|
||||
Raises:
|
||||
CancelledError: If the future was cancelled.
|
||||
TimeoutError: If the future didn't finish executing before the given
|
||||
timeout.
|
||||
"""
|
||||
|
||||
with self._condition:
|
||||
if self._state in [CANCELLED, CANCELLED_AND_NOTIFIED]:
|
||||
raise CancelledError()
|
||||
elif self._state == FINISHED:
|
||||
return self._exception
|
||||
|
||||
self._condition.wait(timeout)
|
||||
|
||||
if self._state in [CANCELLED, CANCELLED_AND_NOTIFIED]:
|
||||
raise CancelledError()
|
||||
elif self._state == FINISHED:
|
||||
return self._exception
|
||||
else:
|
||||
raise TimeoutError()
|
||||
|
||||
# The following methods should only be used by Executors and in tests.
|
||||
def set_running_or_notify_cancel(self):
|
||||
"""Mark the future as running or process any cancel notifications.
|
||||
|
||||
Should only be used by Executor implementations and unit tests.
|
||||
|
||||
If the future has been cancelled (cancel() was called and returned
|
||||
True) then any threads waiting on the future completing (though calls
|
||||
to as_completed() or wait()) are notified and False is returned.
|
||||
|
||||
If the future was not cancelled then it is put in the running state
|
||||
(future calls to running() will return True) and True is returned.
|
||||
|
||||
This method should be called by Executor implementations before
|
||||
executing the work associated with this future. If this method returns
|
||||
False then the work should not be executed.
|
||||
|
||||
Returns:
|
||||
False if the Future was cancelled, True otherwise.
|
||||
|
||||
Raises:
|
||||
RuntimeError: if this method was already called or if set_result()
|
||||
or set_exception() was called.
|
||||
"""
|
||||
with self._condition:
|
||||
if self._state == CANCELLED:
|
||||
self._state = CANCELLED_AND_NOTIFIED
|
||||
for waiter in self._waiters:
|
||||
waiter.add_cancelled(self)
|
||||
# self._condition.notify_all() is not necessary because
|
||||
# self.cancel() triggers a notification.
|
||||
return False
|
||||
elif self._state == PENDING:
|
||||
self._state = RUNNING
|
||||
return True
|
||||
else:
|
||||
LOGGER.critical('Future %s in unexpected state: %s',
|
||||
id(self.future),
|
||||
self.future._state)
|
||||
raise RuntimeError('Future in unexpected state')
|
||||
|
||||
def set_result(self, result):
|
||||
"""Sets the return value of work associated with the future.
|
||||
|
||||
Should only be used by Executor implementations and unit tests.
|
||||
"""
|
||||
with self._condition:
|
||||
self._result = result
|
||||
self._state = FINISHED
|
||||
for waiter in self._waiters:
|
||||
waiter.add_result(self)
|
||||
self._condition.notify_all()
|
||||
self._invoke_callbacks()
|
||||
|
||||
def set_exception(self, exception):
|
||||
"""Sets the result of the future as being the given exception.
|
||||
|
||||
Should only be used by Executor implementations and unit tests.
|
||||
"""
|
||||
with self._condition:
|
||||
self._exception = exception
|
||||
self._state = FINISHED
|
||||
for waiter in self._waiters:
|
||||
waiter.add_exception(self)
|
||||
self._condition.notify_all()
|
||||
self._invoke_callbacks()
|
||||
|
||||
class Executor(object):
|
||||
"""This is an abstract base class for concrete asynchronous executors."""
|
||||
|
||||
def submit(self, fn, *args, **kwargs):
|
||||
"""Submits a callable to be executed with the given arguments.
|
||||
|
||||
Schedules the callable to be executed as fn(*args, **kwargs) and returns
|
||||
a Future instance representing the execution of the callable.
|
||||
|
||||
Returns:
|
||||
A Future representing the given call.
|
||||
"""
|
||||
raise NotImplementedError()
|
||||
|
||||
def map(self, fn, *iterables, **kwargs):
|
||||
"""Returns a iterator equivalent to map(fn, iter).
|
||||
|
||||
Args:
|
||||
fn: A callable that will take take as many arguments as there are
|
||||
passed iterables.
|
||||
timeout: The maximum number of seconds to wait. If None, then there
|
||||
is no limit on the wait time.
|
||||
|
||||
Returns:
|
||||
An iterator equivalent to: map(func, *iterables) but the calls may
|
||||
be evaluated out-of-order.
|
||||
|
||||
Raises:
|
||||
TimeoutError: If the entire result iterator could not be generated
|
||||
before the given timeout.
|
||||
Exception: If fn(*args) raises for any values.
|
||||
"""
|
||||
timeout = kwargs.get('timeout')
|
||||
if timeout is not None:
|
||||
end_time = timeout + time.time()
|
||||
|
||||
fs = [self.submit(fn, *args) for args in zip(*iterables)]
|
||||
|
||||
try:
|
||||
for future in fs:
|
||||
if timeout is None:
|
||||
yield future.result()
|
||||
else:
|
||||
yield future.result(end_time - time.time())
|
||||
finally:
|
||||
for future in fs:
|
||||
future.cancel()
|
||||
|
||||
def shutdown(self, wait=True):
|
||||
"""Clean-up the resources associated with the Executor.
|
||||
|
||||
It is safe to call this method several times. Otherwise, no other
|
||||
methods can be called after this one.
|
||||
|
||||
Args:
|
||||
wait: If True then shutdown will not return until all running
|
||||
futures have finished executing and the resources used by the
|
||||
executor have been reclaimed.
|
||||
"""
|
||||
pass
|
||||
|
||||
def __enter__(self):
|
||||
return self
|
||||
|
||||
def __exit__(self, exc_type, exc_val, exc_tb):
|
||||
self.shutdown(wait=True)
|
||||
return False
|
||||
|
|
@ -1,101 +0,0 @@
|
|||
from keyword import iskeyword as _iskeyword
|
||||
from operator import itemgetter as _itemgetter
|
||||
import sys as _sys
|
||||
|
||||
|
||||
def namedtuple(typename, field_names):
|
||||
"""Returns a new subclass of tuple with named fields.
|
||||
|
||||
>>> Point = namedtuple('Point', 'x y')
|
||||
>>> Point.__doc__ # docstring for the new class
|
||||
'Point(x, y)'
|
||||
>>> p = Point(11, y=22) # instantiate with positional args or keywords
|
||||
>>> p[0] + p[1] # indexable like a plain tuple
|
||||
33
|
||||
>>> x, y = p # unpack like a regular tuple
|
||||
>>> x, y
|
||||
(11, 22)
|
||||
>>> p.x + p.y # fields also accessable by name
|
||||
33
|
||||
>>> d = p._asdict() # convert to a dictionary
|
||||
>>> d['x']
|
||||
11
|
||||
>>> Point(**d) # convert from a dictionary
|
||||
Point(x=11, y=22)
|
||||
>>> p._replace(x=100) # _replace() is like str.replace() but targets named fields
|
||||
Point(x=100, y=22)
|
||||
|
||||
"""
|
||||
|
||||
# Parse and validate the field names. Validation serves two purposes,
|
||||
# generating informative error messages and preventing template injection attacks.
|
||||
if isinstance(field_names, basestring):
|
||||
field_names = field_names.replace(',', ' ').split() # names separated by whitespace and/or commas
|
||||
field_names = tuple(map(str, field_names))
|
||||
for name in (typename,) + field_names:
|
||||
if not all(c.isalnum() or c=='_' for c in name):
|
||||
raise ValueError('Type names and field names can only contain alphanumeric characters and underscores: %r' % name)
|
||||
if _iskeyword(name):
|
||||
raise ValueError('Type names and field names cannot be a keyword: %r' % name)
|
||||
if name[0].isdigit():
|
||||
raise ValueError('Type names and field names cannot start with a number: %r' % name)
|
||||
seen_names = set()
|
||||
for name in field_names:
|
||||
if name.startswith('_'):
|
||||
raise ValueError('Field names cannot start with an underscore: %r' % name)
|
||||
if name in seen_names:
|
||||
raise ValueError('Encountered duplicate field name: %r' % name)
|
||||
seen_names.add(name)
|
||||
|
||||
# Create and fill-in the class template
|
||||
numfields = len(field_names)
|
||||
argtxt = repr(field_names).replace("'", "")[1:-1] # tuple repr without parens or quotes
|
||||
reprtxt = ', '.join('%s=%%r' % name for name in field_names)
|
||||
dicttxt = ', '.join('%r: t[%d]' % (name, pos) for pos, name in enumerate(field_names))
|
||||
template = '''class %(typename)s(tuple):
|
||||
'%(typename)s(%(argtxt)s)' \n
|
||||
__slots__ = () \n
|
||||
_fields = %(field_names)r \n
|
||||
def __new__(_cls, %(argtxt)s):
|
||||
return _tuple.__new__(_cls, (%(argtxt)s)) \n
|
||||
@classmethod
|
||||
def _make(cls, iterable, new=tuple.__new__, len=len):
|
||||
'Make a new %(typename)s object from a sequence or iterable'
|
||||
result = new(cls, iterable)
|
||||
if len(result) != %(numfields)d:
|
||||
raise TypeError('Expected %(numfields)d arguments, got %%d' %% len(result))
|
||||
return result \n
|
||||
def __repr__(self):
|
||||
return '%(typename)s(%(reprtxt)s)' %% self \n
|
||||
def _asdict(t):
|
||||
'Return a new dict which maps field names to their values'
|
||||
return {%(dicttxt)s} \n
|
||||
def _replace(_self, **kwds):
|
||||
'Return a new %(typename)s object replacing specified fields with new values'
|
||||
result = _self._make(map(kwds.pop, %(field_names)r, _self))
|
||||
if kwds:
|
||||
raise ValueError('Got unexpected field names: %%r' %% kwds.keys())
|
||||
return result \n
|
||||
def __getnewargs__(self):
|
||||
return tuple(self) \n\n''' % locals()
|
||||
for i, name in enumerate(field_names):
|
||||
template += ' %s = _property(_itemgetter(%d))\n' % (name, i)
|
||||
|
||||
# Execute the template string in a temporary namespace and
|
||||
# support tracing utilities by setting a value for frame.f_globals['__name__']
|
||||
namespace = dict(_itemgetter=_itemgetter, __name__='namedtuple_%s' % typename,
|
||||
_property=property, _tuple=tuple)
|
||||
try:
|
||||
exec(template, namespace)
|
||||
except SyntaxError:
|
||||
e = _sys.exc_info()[1]
|
||||
raise SyntaxError(e.message + ':\n' + template)
|
||||
result = namespace[typename]
|
||||
|
||||
# For pickling to work, the __module__ variable needs to be set to the frame
|
||||
# where the named tuple is created. Bypass this step in enviroments where
|
||||
# sys._getframe is not defined (Jython for example).
|
||||
if hasattr(_sys, '_getframe'):
|
||||
result.__module__ = _sys._getframe(1).f_globals.get('__name__', '__main__')
|
||||
|
||||
return result
|
||||
|
|
@ -1,345 +0,0 @@
|
|||
# Copyright 2009 Brian Quinlan. All Rights Reserved.
|
||||
# Licensed to PSF under a Contributor Agreement.
|
||||
|
||||
"""Implements ProcessPoolExecutor.
|
||||
|
||||
The follow diagram and text describe the data-flow through the system:
|
||||
|
||||
|======================= In-process =====================|== Out-of-process ==|
|
||||
|
||||
+----------+ +----------+ +--------+ +-----------+ +---------+
|
||||
| | => | Work Ids | => | | => | Call Q | => | |
|
||||
| | +----------+ | | +-----------+ | |
|
||||
| | | ... | | | | ... | | |
|
||||
| | | 6 | | | | 5, call() | | |
|
||||
| | | 7 | | | | ... | | |
|
||||
| Process | | ... | | Local | +-----------+ | Process |
|
||||
| Pool | +----------+ | Worker | | #1..n |
|
||||
| Executor | | Thread | | |
|
||||
| | +----------- + | | +-----------+ | |
|
||||
| | <=> | Work Items | <=> | | <= | Result Q | <= | |
|
||||
| | +------------+ | | +-----------+ | |
|
||||
| | | 6: call() | | | | ... | | |
|
||||
| | | future | | | | 4, result | | |
|
||||
| | | ... | | | | 3, except | | |
|
||||
+----------+ +------------+ +--------+ +-----------+ +---------+
|
||||
|
||||
Executor.submit() called:
|
||||
- creates a uniquely numbered _WorkItem and adds it to the "Work Items" dict
|
||||
- adds the id of the _WorkItem to the "Work Ids" queue
|
||||
|
||||
Local worker thread:
|
||||
- reads work ids from the "Work Ids" queue and looks up the corresponding
|
||||
WorkItem from the "Work Items" dict: if the work item has been cancelled then
|
||||
it is simply removed from the dict, otherwise it is repackaged as a
|
||||
_CallItem and put in the "Call Q". New _CallItems are put in the "Call Q"
|
||||
until "Call Q" is full. NOTE: the size of the "Call Q" is kept small because
|
||||
calls placed in the "Call Q" can no longer be cancelled with Future.cancel().
|
||||
- reads _ResultItems from "Result Q", updates the future stored in the
|
||||
"Work Items" dict and deletes the dict entry
|
||||
|
||||
Process #1..n:
|
||||
- reads _CallItems from "Call Q", executes the calls, and puts the resulting
|
||||
_ResultItems in "Request Q"
|
||||
"""
|
||||
|
||||
from __future__ import with_statement
|
||||
import atexit
|
||||
import multiprocessing
|
||||
import threading
|
||||
import weakref
|
||||
import sys
|
||||
|
||||
from concurrent.futures import _base
|
||||
|
||||
try:
|
||||
import queue
|
||||
except ImportError:
|
||||
import Queue as queue
|
||||
|
||||
__author__ = 'Brian Quinlan (brian@sweetapp.com)'
|
||||
|
||||
# Workers are created as daemon threads and processes. This is done to allow the
|
||||
# interpreter to exit when there are still idle processes in a
|
||||
# ProcessPoolExecutor's process pool (i.e. shutdown() was not called). However,
|
||||
# allowing workers to die with the interpreter has two undesirable properties:
|
||||
# - The workers would still be running during interpretor shutdown,
|
||||
# meaning that they would fail in unpredictable ways.
|
||||
# - The workers could be killed while evaluating a work item, which could
|
||||
# be bad if the callable being evaluated has external side-effects e.g.
|
||||
# writing to a file.
|
||||
#
|
||||
# To work around this problem, an exit handler is installed which tells the
|
||||
# workers to exit when their work queues are empty and then waits until the
|
||||
# threads/processes finish.
|
||||
|
||||
_thread_references = set()
|
||||
_shutdown = False
|
||||
|
||||
def _python_exit():
|
||||
global _shutdown
|
||||
_shutdown = True
|
||||
for thread_reference in _thread_references:
|
||||
thread = thread_reference()
|
||||
if thread is not None:
|
||||
thread.join()
|
||||
|
||||
def _remove_dead_thread_references():
|
||||
"""Remove inactive threads from _thread_references.
|
||||
|
||||
Should be called periodically to prevent memory leaks in scenarios such as:
|
||||
>>> while True:
|
||||
>>> ... t = ThreadPoolExecutor(max_workers=5)
|
||||
>>> ... t.map(int, ['1', '2', '3', '4', '5'])
|
||||
"""
|
||||
for thread_reference in set(_thread_references):
|
||||
if thread_reference() is None:
|
||||
_thread_references.discard(thread_reference)
|
||||
|
||||
# Controls how many more calls than processes will be queued in the call queue.
|
||||
# A smaller number will mean that processes spend more time idle waiting for
|
||||
# work while a larger number will make Future.cancel() succeed less frequently
|
||||
# (Futures in the call queue cannot be cancelled).
|
||||
EXTRA_QUEUED_CALLS = 1
|
||||
|
||||
class _WorkItem(object):
|
||||
def __init__(self, future, fn, args, kwargs):
|
||||
self.future = future
|
||||
self.fn = fn
|
||||
self.args = args
|
||||
self.kwargs = kwargs
|
||||
|
||||
class _ResultItem(object):
|
||||
def __init__(self, work_id, exception=None, result=None):
|
||||
self.work_id = work_id
|
||||
self.exception = exception
|
||||
self.result = result
|
||||
|
||||
class _CallItem(object):
|
||||
def __init__(self, work_id, fn, args, kwargs):
|
||||
self.work_id = work_id
|
||||
self.fn = fn
|
||||
self.args = args
|
||||
self.kwargs = kwargs
|
||||
|
||||
def _process_worker(call_queue, result_queue, shutdown):
|
||||
"""Evaluates calls from call_queue and places the results in result_queue.
|
||||
|
||||
This worker is run in a seperate process.
|
||||
|
||||
Args:
|
||||
call_queue: A multiprocessing.Queue of _CallItems that will be read and
|
||||
evaluated by the worker.
|
||||
result_queue: A multiprocessing.Queue of _ResultItems that will written
|
||||
to by the worker.
|
||||
shutdown: A multiprocessing.Event that will be set as a signal to the
|
||||
worker that it should exit when call_queue is empty.
|
||||
"""
|
||||
while True:
|
||||
try:
|
||||
call_item = call_queue.get(block=True, timeout=0.1)
|
||||
except queue.Empty:
|
||||
if shutdown.is_set():
|
||||
return
|
||||
else:
|
||||
try:
|
||||
r = call_item.fn(*call_item.args, **call_item.kwargs)
|
||||
except BaseException:
|
||||
e = sys.exc_info()[1]
|
||||
result_queue.put(_ResultItem(call_item.work_id,
|
||||
exception=e))
|
||||
else:
|
||||
result_queue.put(_ResultItem(call_item.work_id,
|
||||
result=r))
|
||||
|
||||
def _add_call_item_to_queue(pending_work_items,
|
||||
work_ids,
|
||||
call_queue):
|
||||
"""Fills call_queue with _WorkItems from pending_work_items.
|
||||
|
||||
This function never blocks.
|
||||
|
||||
Args:
|
||||
pending_work_items: A dict mapping work ids to _WorkItems e.g.
|
||||
{5: <_WorkItem...>, 6: <_WorkItem...>, ...}
|
||||
work_ids: A queue.Queue of work ids e.g. Queue([5, 6, ...]). Work ids
|
||||
are consumed and the corresponding _WorkItems from
|
||||
pending_work_items are transformed into _CallItems and put in
|
||||
call_queue.
|
||||
call_queue: A multiprocessing.Queue that will be filled with _CallItems
|
||||
derived from _WorkItems.
|
||||
"""
|
||||
while True:
|
||||
if call_queue.full():
|
||||
return
|
||||
try:
|
||||
work_id = work_ids.get(block=False)
|
||||
except queue.Empty:
|
||||
return
|
||||
else:
|
||||
work_item = pending_work_items[work_id]
|
||||
|
||||
if work_item.future.set_running_or_notify_cancel():
|
||||
call_queue.put(_CallItem(work_id,
|
||||
work_item.fn,
|
||||
work_item.args,
|
||||
work_item.kwargs),
|
||||
block=True)
|
||||
else:
|
||||
del pending_work_items[work_id]
|
||||
continue
|
||||
|
||||
def _queue_manangement_worker(executor_reference,
|
||||
processes,
|
||||
pending_work_items,
|
||||
work_ids_queue,
|
||||
call_queue,
|
||||
result_queue,
|
||||
shutdown_process_event):
|
||||
"""Manages the communication between this process and the worker processes.
|
||||
|
||||
This function is run in a local thread.
|
||||
|
||||
Args:
|
||||
executor_reference: A weakref.ref to the ProcessPoolExecutor that owns
|
||||
this thread. Used to determine if the ProcessPoolExecutor has been
|
||||
garbage collected and that this function can exit.
|
||||
process: A list of the multiprocessing.Process instances used as
|
||||
workers.
|
||||
pending_work_items: A dict mapping work ids to _WorkItems e.g.
|
||||
{5: <_WorkItem...>, 6: <_WorkItem...>, ...}
|
||||
work_ids_queue: A queue.Queue of work ids e.g. Queue([5, 6, ...]).
|
||||
call_queue: A multiprocessing.Queue that will be filled with _CallItems
|
||||
derived from _WorkItems for processing by the process workers.
|
||||
result_queue: A multiprocessing.Queue of _ResultItems generated by the
|
||||
process workers.
|
||||
shutdown_process_event: A multiprocessing.Event used to signal the
|
||||
process workers that they should exit when their work queue is
|
||||
empty.
|
||||
"""
|
||||
while True:
|
||||
_add_call_item_to_queue(pending_work_items,
|
||||
work_ids_queue,
|
||||
call_queue)
|
||||
|
||||
try:
|
||||
result_item = result_queue.get(block=True, timeout=0.1)
|
||||
except queue.Empty:
|
||||
executor = executor_reference()
|
||||
# No more work items can be added if:
|
||||
# - The interpreter is shutting down OR
|
||||
# - The executor that owns this worker has been collected OR
|
||||
# - The executor that owns this worker has been shutdown.
|
||||
if _shutdown or executor is None or executor._shutdown_thread:
|
||||
# Since no new work items can be added, it is safe to shutdown
|
||||
# this thread if there are no pending work items.
|
||||
if not pending_work_items:
|
||||
shutdown_process_event.set()
|
||||
|
||||
# If .join() is not called on the created processes then
|
||||
# some multiprocessing.Queue methods may deadlock on Mac OS
|
||||
# X.
|
||||
for p in processes:
|
||||
p.join()
|
||||
return
|
||||
del executor
|
||||
else:
|
||||
work_item = pending_work_items[result_item.work_id]
|
||||
del pending_work_items[result_item.work_id]
|
||||
|
||||
if result_item.exception:
|
||||
work_item.future.set_exception(result_item.exception)
|
||||
else:
|
||||
work_item.future.set_result(result_item.result)
|
||||
|
||||
class ProcessPoolExecutor(_base.Executor):
|
||||
def __init__(self, max_workers=None):
|
||||
"""Initializes a new ProcessPoolExecutor instance.
|
||||
|
||||
Args:
|
||||
max_workers: The maximum number of processes that can be used to
|
||||
execute the given calls. If None or not given then as many
|
||||
worker processes will be created as the machine has processors.
|
||||
"""
|
||||
_remove_dead_thread_references()
|
||||
|
||||
if max_workers is None:
|
||||
self._max_workers = multiprocessing.cpu_count()
|
||||
else:
|
||||
self._max_workers = max_workers
|
||||
|
||||
# Make the call queue slightly larger than the number of processes to
|
||||
# prevent the worker processes from idling. But don't make it too big
|
||||
# because futures in the call queue cannot be cancelled.
|
||||
self._call_queue = multiprocessing.Queue(self._max_workers +
|
||||
EXTRA_QUEUED_CALLS)
|
||||
self._result_queue = multiprocessing.Queue()
|
||||
self._work_ids = queue.Queue()
|
||||
self._queue_management_thread = None
|
||||
self._processes = set()
|
||||
|
||||
# Shutdown is a two-step process.
|
||||
self._shutdown_thread = False
|
||||
self._shutdown_process_event = multiprocessing.Event()
|
||||
self._shutdown_lock = threading.Lock()
|
||||
self._queue_count = 0
|
||||
self._pending_work_items = {}
|
||||
|
||||
def _start_queue_management_thread(self):
|
||||
if self._queue_management_thread is None:
|
||||
self._queue_management_thread = threading.Thread(
|
||||
target=_queue_manangement_worker,
|
||||
args=(weakref.ref(self),
|
||||
self._processes,
|
||||
self._pending_work_items,
|
||||
self._work_ids,
|
||||
self._call_queue,
|
||||
self._result_queue,
|
||||
self._shutdown_process_event))
|
||||
self._queue_management_thread.daemon = True
|
||||
self._queue_management_thread.start()
|
||||
_thread_references.add(weakref.ref(self._queue_management_thread))
|
||||
|
||||
def _adjust_process_count(self):
|
||||
for _ in range(len(self._processes), self._max_workers):
|
||||
p = multiprocessing.Process(
|
||||
target=_process_worker,
|
||||
args=(self._call_queue,
|
||||
self._result_queue,
|
||||
self._shutdown_process_event))
|
||||
p.start()
|
||||
self._processes.add(p)
|
||||
|
||||
def submit(self, fn, *args, **kwargs):
|
||||
with self._shutdown_lock:
|
||||
if self._shutdown_thread:
|
||||
raise RuntimeError('cannot schedule new futures after shutdown')
|
||||
|
||||
f = _base.Future()
|
||||
w = _WorkItem(f, fn, args, kwargs)
|
||||
|
||||
self._pending_work_items[self._queue_count] = w
|
||||
self._work_ids.put(self._queue_count)
|
||||
self._queue_count += 1
|
||||
|
||||
self._start_queue_management_thread()
|
||||
self._adjust_process_count()
|
||||
return f
|
||||
submit.__doc__ = _base.Executor.submit.__doc__
|
||||
|
||||
def shutdown(self, wait=True):
|
||||
with self._shutdown_lock:
|
||||
self._shutdown_thread = True
|
||||
if wait:
|
||||
if self._queue_management_thread:
|
||||
self._queue_management_thread.join()
|
||||
# To reduce the risk of openning too many files, remove references to
|
||||
# objects that use file descriptors.
|
||||
self._queue_management_thread = None
|
||||
self._call_queue = None
|
||||
self._result_queue = None
|
||||
self._shutdown_process_event = None
|
||||
self._processes = None
|
||||
shutdown.__doc__ = _base.Executor.shutdown.__doc__
|
||||
|
||||
atexit.register(_python_exit)
|
||||
|
|
@ -1,144 +0,0 @@
|
|||
# Copyright 2009 Brian Quinlan. All Rights Reserved.
|
||||
# Licensed to PSF under a Contributor Agreement.
|
||||
|
||||
"""Implements ThreadPoolExecutor."""
|
||||
|
||||
from __future__ import with_statement
|
||||
import atexit
|
||||
import threading
|
||||
import weakref
|
||||
import sys
|
||||
|
||||
from concurrent.futures import _base
|
||||
|
||||
try:
|
||||
import queue
|
||||
except ImportError:
|
||||
import Queue as queue
|
||||
|
||||
__author__ = 'Brian Quinlan (brian@sweetapp.com)'
|
||||
|
||||
# Workers are created as daemon threads. This is done to allow the interpreter
|
||||
# to exit when there are still idle threads in a ThreadPoolExecutor's thread
|
||||
# pool (i.e. shutdown() was not called). However, allowing workers to die with
|
||||
# the interpreter has two undesirable properties:
|
||||
# - The workers would still be running during interpretor shutdown,
|
||||
# meaning that they would fail in unpredictable ways.
|
||||
# - The workers could be killed while evaluating a work item, which could
|
||||
# be bad if the callable being evaluated has external side-effects e.g.
|
||||
# writing to a file.
|
||||
#
|
||||
# To work around this problem, an exit handler is installed which tells the
|
||||
# workers to exit when their work queues are empty and then waits until the
|
||||
# threads finish.
|
||||
|
||||
_thread_references = set()
|
||||
_shutdown = False
|
||||
|
||||
def _python_exit():
|
||||
global _shutdown
|
||||
_shutdown = True
|
||||
for thread_reference in _thread_references:
|
||||
thread = thread_reference()
|
||||
if thread is not None:
|
||||
thread.join()
|
||||
|
||||
def _remove_dead_thread_references():
|
||||
"""Remove inactive threads from _thread_references.
|
||||
|
||||
Should be called periodically to prevent memory leaks in scenarios such as:
|
||||
>>> while True:
|
||||
... t = ThreadPoolExecutor(max_workers=5)
|
||||
... t.map(int, ['1', '2', '3', '4', '5'])
|
||||
"""
|
||||
for thread_reference in set(_thread_references):
|
||||
if thread_reference() is None:
|
||||
_thread_references.discard(thread_reference)
|
||||
|
||||
atexit.register(_python_exit)
|
||||
|
||||
class _WorkItem(object):
|
||||
def __init__(self, future, fn, args, kwargs):
|
||||
self.future = future
|
||||
self.fn = fn
|
||||
self.args = args
|
||||
self.kwargs = kwargs
|
||||
|
||||
def run(self):
|
||||
if not self.future.set_running_or_notify_cancel():
|
||||
return
|
||||
|
||||
try:
|
||||
result = self.fn(*self.args, **self.kwargs)
|
||||
except BaseException:
|
||||
e = sys.exc_info()[1]
|
||||
self.future.set_exception(e)
|
||||
else:
|
||||
self.future.set_result(result)
|
||||
|
||||
def _worker(executor_reference, work_queue):
|
||||
try:
|
||||
while True:
|
||||
try:
|
||||
work_item = work_queue.get(block=True, timeout=0.1)
|
||||
except queue.Empty:
|
||||
executor = executor_reference()
|
||||
# Exit if:
|
||||
# - The interpreter is shutting down OR
|
||||
# - The executor that owns the worker has been collected OR
|
||||
# - The executor that owns the worker has been shutdown.
|
||||
if _shutdown or executor is None or executor._shutdown:
|
||||
return
|
||||
del executor
|
||||
else:
|
||||
work_item.run()
|
||||
except BaseException:
|
||||
_base.LOGGER.critical('Exception in worker', exc_info=True)
|
||||
|
||||
class ThreadPoolExecutor(_base.Executor):
|
||||
def __init__(self, max_workers):
|
||||
"""Initializes a new ThreadPoolExecutor instance.
|
||||
|
||||
Args:
|
||||
max_workers: The maximum number of threads that can be used to
|
||||
execute the given calls.
|
||||
"""
|
||||
_remove_dead_thread_references()
|
||||
|
||||
self._max_workers = max_workers
|
||||
self._work_queue = queue.Queue()
|
||||
self._threads = set()
|
||||
self._shutdown = False
|
||||
self._shutdown_lock = threading.Lock()
|
||||
|
||||
def submit(self, fn, *args, **kwargs):
|
||||
with self._shutdown_lock:
|
||||
if self._shutdown:
|
||||
raise RuntimeError('cannot schedule new futures after shutdown')
|
||||
|
||||
f = _base.Future()
|
||||
w = _WorkItem(f, fn, args, kwargs)
|
||||
|
||||
self._work_queue.put(w)
|
||||
self._adjust_thread_count()
|
||||
return f
|
||||
submit.__doc__ = _base.Executor.submit.__doc__
|
||||
|
||||
def _adjust_thread_count(self):
|
||||
# TODO(bquinlan): Should avoid creating new threads if there are more
|
||||
# idle threads than items in the work queue.
|
||||
if len(self._threads) < self._max_workers:
|
||||
t = threading.Thread(target=_worker,
|
||||
args=(weakref.ref(self), self._work_queue))
|
||||
t.daemon = True
|
||||
t.start()
|
||||
self._threads.add(t)
|
||||
_thread_references.add(weakref.ref(t))
|
||||
|
||||
def shutdown(self, wait=True):
|
||||
with self._shutdown_lock:
|
||||
self._shutdown = True
|
||||
if wait:
|
||||
for t in self._threads:
|
||||
t.join()
|
||||
shutdown.__doc__ = _base.Executor.shutdown.__doc__
|
||||
Loading…
Reference in New Issue