mercurial/worker.py
author Gregory Szorc <gregory.szorc@gmail.com>
Mon, 05 Oct 2015 16:34:47 -0700
changeset 26479 46143f31290e
parent 26063 d29859cfcfc2
child 26568 c0501c26b05c
permissions -rw-r--r--
util.chunkbuffer: refactor chunk handling logic This will make the next patch easier to read. It provides no benefit on its own.
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
18635
fed06dd07665 worker: count the number of CPUs
Bryan O'Sullivan <bryano@fb.com>
parents:
diff changeset
     1
# worker.py - master-slave parallelism support
fed06dd07665 worker: count the number of CPUs
Bryan O'Sullivan <bryano@fb.com>
parents:
diff changeset
     2
#
fed06dd07665 worker: count the number of CPUs
Bryan O'Sullivan <bryano@fb.com>
parents:
diff changeset
     3
# Copyright 2013 Facebook, Inc.
fed06dd07665 worker: count the number of CPUs
Bryan O'Sullivan <bryano@fb.com>
parents:
diff changeset
     4
#
fed06dd07665 worker: count the number of CPUs
Bryan O'Sullivan <bryano@fb.com>
parents:
diff changeset
     5
# This software may be used and distributed according to the terms of the
fed06dd07665 worker: count the number of CPUs
Bryan O'Sullivan <bryano@fb.com>
parents:
diff changeset
     6
# GNU General Public License version 2 or any later version.
fed06dd07665 worker: count the number of CPUs
Bryan O'Sullivan <bryano@fb.com>
parents:
diff changeset
     7
25992
2d76f8a2d831 worker: use absolute_import
Gregory Szorc <gregory.szorc@gmail.com>
parents: 25660
diff changeset
     8
from __future__ import absolute_import
2d76f8a2d831 worker: use absolute_import
Gregory Szorc <gregory.szorc@gmail.com>
parents: 25660
diff changeset
     9
2d76f8a2d831 worker: use absolute_import
Gregory Szorc <gregory.szorc@gmail.com>
parents: 25660
diff changeset
    10
import errno
26063
d29859cfcfc2 worker: use multiprocessing to find cpu count
Gregory Szorc <gregory.szorc@gmail.com>
parents: 25992
diff changeset
    11
import multiprocessing
25992
2d76f8a2d831 worker: use absolute_import
Gregory Szorc <gregory.szorc@gmail.com>
parents: 25660
diff changeset
    12
import os
2d76f8a2d831 worker: use absolute_import
Gregory Szorc <gregory.szorc@gmail.com>
parents: 25660
diff changeset
    13
import signal
2d76f8a2d831 worker: use absolute_import
Gregory Szorc <gregory.szorc@gmail.com>
parents: 25660
diff changeset
    14
import sys
2d76f8a2d831 worker: use absolute_import
Gregory Szorc <gregory.szorc@gmail.com>
parents: 25660
diff changeset
    15
import threading
2d76f8a2d831 worker: use absolute_import
Gregory Szorc <gregory.szorc@gmail.com>
parents: 25660
diff changeset
    16
2d76f8a2d831 worker: use absolute_import
Gregory Szorc <gregory.szorc@gmail.com>
parents: 25660
diff changeset
    17
from .i18n import _
2d76f8a2d831 worker: use absolute_import
Gregory Szorc <gregory.szorc@gmail.com>
parents: 25660
diff changeset
    18
from . import util
18635
fed06dd07665 worker: count the number of CPUs
Bryan O'Sullivan <bryano@fb.com>
parents:
diff changeset
    19
fed06dd07665 worker: count the number of CPUs
Bryan O'Sullivan <bryano@fb.com>
parents:
diff changeset
    20
def countcpus():
fed06dd07665 worker: count the number of CPUs
Bryan O'Sullivan <bryano@fb.com>
parents:
diff changeset
    21
    '''try to count the number of CPUs on the system'''
fed06dd07665 worker: count the number of CPUs
Bryan O'Sullivan <bryano@fb.com>
parents:
diff changeset
    22
    try:
26063
d29859cfcfc2 worker: use multiprocessing to find cpu count
Gregory Szorc <gregory.szorc@gmail.com>
parents: 25992
diff changeset
    23
        return multiprocessing.cpu_count()
d29859cfcfc2 worker: use multiprocessing to find cpu count
Gregory Szorc <gregory.szorc@gmail.com>
parents: 25992
diff changeset
    24
    except NotImplementedError:
d29859cfcfc2 worker: use multiprocessing to find cpu count
Gregory Szorc <gregory.szorc@gmail.com>
parents: 25992
diff changeset
    25
        return 1
18636
dcb27c153a40 worker: estimate whether it's worth running a task in parallel
Bryan O'Sullivan <bryano@fb.com>
parents: 18635
diff changeset
    26
dcb27c153a40 worker: estimate whether it's worth running a task in parallel
Bryan O'Sullivan <bryano@fb.com>
parents: 18635
diff changeset
    27
def _numworkers(ui):
dcb27c153a40 worker: estimate whether it's worth running a task in parallel
Bryan O'Sullivan <bryano@fb.com>
parents: 18635
diff changeset
    28
    s = ui.config('worker', 'numcpus')
dcb27c153a40 worker: estimate whether it's worth running a task in parallel
Bryan O'Sullivan <bryano@fb.com>
parents: 18635
diff changeset
    29
    if s:
dcb27c153a40 worker: estimate whether it's worth running a task in parallel
Bryan O'Sullivan <bryano@fb.com>
parents: 18635
diff changeset
    30
        try:
dcb27c153a40 worker: estimate whether it's worth running a task in parallel
Bryan O'Sullivan <bryano@fb.com>
parents: 18635
diff changeset
    31
            n = int(s)
dcb27c153a40 worker: estimate whether it's worth running a task in parallel
Bryan O'Sullivan <bryano@fb.com>
parents: 18635
diff changeset
    32
            if n >= 1:
dcb27c153a40 worker: estimate whether it's worth running a task in parallel
Bryan O'Sullivan <bryano@fb.com>
parents: 18635
diff changeset
    33
                return n
dcb27c153a40 worker: estimate whether it's worth running a task in parallel
Bryan O'Sullivan <bryano@fb.com>
parents: 18635
diff changeset
    34
        except ValueError:
dcb27c153a40 worker: estimate whether it's worth running a task in parallel
Bryan O'Sullivan <bryano@fb.com>
parents: 18635
diff changeset
    35
            raise util.Abort(_('number of cpus must be an integer'))
dcb27c153a40 worker: estimate whether it's worth running a task in parallel
Bryan O'Sullivan <bryano@fb.com>
parents: 18635
diff changeset
    36
    return min(max(countcpus(), 4), 32)
dcb27c153a40 worker: estimate whether it's worth running a task in parallel
Bryan O'Sullivan <bryano@fb.com>
parents: 18635
diff changeset
    37
dcb27c153a40 worker: estimate whether it's worth running a task in parallel
Bryan O'Sullivan <bryano@fb.com>
parents: 18635
diff changeset
    38
if os.name == 'posix':
dcb27c153a40 worker: estimate whether it's worth running a task in parallel
Bryan O'Sullivan <bryano@fb.com>
parents: 18635
diff changeset
    39
    _startupcost = 0.01
dcb27c153a40 worker: estimate whether it's worth running a task in parallel
Bryan O'Sullivan <bryano@fb.com>
parents: 18635
diff changeset
    40
else:
dcb27c153a40 worker: estimate whether it's worth running a task in parallel
Bryan O'Sullivan <bryano@fb.com>
parents: 18635
diff changeset
    41
    _startupcost = 1e30
dcb27c153a40 worker: estimate whether it's worth running a task in parallel
Bryan O'Sullivan <bryano@fb.com>
parents: 18635
diff changeset
    42
dcb27c153a40 worker: estimate whether it's worth running a task in parallel
Bryan O'Sullivan <bryano@fb.com>
parents: 18635
diff changeset
    43
def worthwhile(ui, costperop, nops):
dcb27c153a40 worker: estimate whether it's worth running a task in parallel
Bryan O'Sullivan <bryano@fb.com>
parents: 18635
diff changeset
    44
    '''try to determine whether the benefit of multiple processes can
dcb27c153a40 worker: estimate whether it's worth running a task in parallel
Bryan O'Sullivan <bryano@fb.com>
parents: 18635
diff changeset
    45
    outweigh the cost of starting them'''
dcb27c153a40 worker: estimate whether it's worth running a task in parallel
Bryan O'Sullivan <bryano@fb.com>
parents: 18635
diff changeset
    46
    linear = costperop * nops
dcb27c153a40 worker: estimate whether it's worth running a task in parallel
Bryan O'Sullivan <bryano@fb.com>
parents: 18635
diff changeset
    47
    workers = _numworkers(ui)
dcb27c153a40 worker: estimate whether it's worth running a task in parallel
Bryan O'Sullivan <bryano@fb.com>
parents: 18635
diff changeset
    48
    benefit = linear - (_startupcost * workers + linear / workers)
dcb27c153a40 worker: estimate whether it's worth running a task in parallel
Bryan O'Sullivan <bryano@fb.com>
parents: 18635
diff changeset
    49
    return benefit >= 0.15
18637
ac4dbceeb14a worker: partition a list (of tasks) into equal-sized chunks
Bryan O'Sullivan <bryano@fb.com>
parents: 18636
diff changeset
    50
18638
047110c0e2a8 worker: allow a function to be run in multiple worker processes
Bryan O'Sullivan <bryano@fb.com>
parents: 18637
diff changeset
    51
def worker(ui, costperarg, func, staticargs, args):
047110c0e2a8 worker: allow a function to be run in multiple worker processes
Bryan O'Sullivan <bryano@fb.com>
parents: 18637
diff changeset
    52
    '''run a function, possibly in parallel in multiple worker
047110c0e2a8 worker: allow a function to be run in multiple worker processes
Bryan O'Sullivan <bryano@fb.com>
parents: 18637
diff changeset
    53
    processes.
047110c0e2a8 worker: allow a function to be run in multiple worker processes
Bryan O'Sullivan <bryano@fb.com>
parents: 18637
diff changeset
    54
047110c0e2a8 worker: allow a function to be run in multiple worker processes
Bryan O'Sullivan <bryano@fb.com>
parents: 18637
diff changeset
    55
    returns a progress iterator
047110c0e2a8 worker: allow a function to be run in multiple worker processes
Bryan O'Sullivan <bryano@fb.com>
parents: 18637
diff changeset
    56
047110c0e2a8 worker: allow a function to be run in multiple worker processes
Bryan O'Sullivan <bryano@fb.com>
parents: 18637
diff changeset
    57
    costperarg - cost of a single task
047110c0e2a8 worker: allow a function to be run in multiple worker processes
Bryan O'Sullivan <bryano@fb.com>
parents: 18637
diff changeset
    58
047110c0e2a8 worker: allow a function to be run in multiple worker processes
Bryan O'Sullivan <bryano@fb.com>
parents: 18637
diff changeset
    59
    func - function to run
047110c0e2a8 worker: allow a function to be run in multiple worker processes
Bryan O'Sullivan <bryano@fb.com>
parents: 18637
diff changeset
    60
047110c0e2a8 worker: allow a function to be run in multiple worker processes
Bryan O'Sullivan <bryano@fb.com>
parents: 18637
diff changeset
    61
    staticargs - arguments to pass to every invocation of the function
047110c0e2a8 worker: allow a function to be run in multiple worker processes
Bryan O'Sullivan <bryano@fb.com>
parents: 18637
diff changeset
    62
047110c0e2a8 worker: allow a function to be run in multiple worker processes
Bryan O'Sullivan <bryano@fb.com>
parents: 18637
diff changeset
    63
    args - arguments to split into chunks, to pass to individual
047110c0e2a8 worker: allow a function to be run in multiple worker processes
Bryan O'Sullivan <bryano@fb.com>
parents: 18637
diff changeset
    64
    workers
047110c0e2a8 worker: allow a function to be run in multiple worker processes
Bryan O'Sullivan <bryano@fb.com>
parents: 18637
diff changeset
    65
    '''
047110c0e2a8 worker: allow a function to be run in multiple worker processes
Bryan O'Sullivan <bryano@fb.com>
parents: 18637
diff changeset
    66
    if worthwhile(ui, costperarg, len(args)):
047110c0e2a8 worker: allow a function to be run in multiple worker processes
Bryan O'Sullivan <bryano@fb.com>
parents: 18637
diff changeset
    67
        return _platformworker(ui, func, staticargs, args)
047110c0e2a8 worker: allow a function to be run in multiple worker processes
Bryan O'Sullivan <bryano@fb.com>
parents: 18637
diff changeset
    68
    return func(*staticargs + (args,))
047110c0e2a8 worker: allow a function to be run in multiple worker processes
Bryan O'Sullivan <bryano@fb.com>
parents: 18637
diff changeset
    69
047110c0e2a8 worker: allow a function to be run in multiple worker processes
Bryan O'Sullivan <bryano@fb.com>
parents: 18637
diff changeset
    70
def _posixworker(ui, func, staticargs, args):
047110c0e2a8 worker: allow a function to be run in multiple worker processes
Bryan O'Sullivan <bryano@fb.com>
parents: 18637
diff changeset
    71
    rfd, wfd = os.pipe()
047110c0e2a8 worker: allow a function to be run in multiple worker processes
Bryan O'Sullivan <bryano@fb.com>
parents: 18637
diff changeset
    72
    workers = _numworkers(ui)
18708
86524a70c0f6 worker: fix a race in SIGINT handling
Bryan O'Sullivan <bryano@fb.com>
parents: 18707
diff changeset
    73
    oldhandler = signal.getsignal(signal.SIGINT)
86524a70c0f6 worker: fix a race in SIGINT handling
Bryan O'Sullivan <bryano@fb.com>
parents: 18707
diff changeset
    74
    signal.signal(signal.SIGINT, signal.SIG_IGN)
18709
9955fc5ee24b worker: handle worker failures more aggressively
Bryan O'Sullivan <bryano@fb.com>
parents: 18708
diff changeset
    75
    pids, problem = [], [0]
18638
047110c0e2a8 worker: allow a function to be run in multiple worker processes
Bryan O'Sullivan <bryano@fb.com>
parents: 18637
diff changeset
    76
    for pargs in partition(args, workers):
047110c0e2a8 worker: allow a function to be run in multiple worker processes
Bryan O'Sullivan <bryano@fb.com>
parents: 18637
diff changeset
    77
        pid = os.fork()
047110c0e2a8 worker: allow a function to be run in multiple worker processes
Bryan O'Sullivan <bryano@fb.com>
parents: 18637
diff changeset
    78
        if pid == 0:
18708
86524a70c0f6 worker: fix a race in SIGINT handling
Bryan O'Sullivan <bryano@fb.com>
parents: 18707
diff changeset
    79
            signal.signal(signal.SIGINT, oldhandler)
18638
047110c0e2a8 worker: allow a function to be run in multiple worker processes
Bryan O'Sullivan <bryano@fb.com>
parents: 18637
diff changeset
    80
            try:
047110c0e2a8 worker: allow a function to be run in multiple worker processes
Bryan O'Sullivan <bryano@fb.com>
parents: 18637
diff changeset
    81
                os.close(rfd)
047110c0e2a8 worker: allow a function to be run in multiple worker processes
Bryan O'Sullivan <bryano@fb.com>
parents: 18637
diff changeset
    82
                for i, item in func(*(staticargs + (pargs,))):
047110c0e2a8 worker: allow a function to be run in multiple worker processes
Bryan O'Sullivan <bryano@fb.com>
parents: 18637
diff changeset
    83
                    os.write(wfd, '%d %s\n' % (i, item))
047110c0e2a8 worker: allow a function to be run in multiple worker processes
Bryan O'Sullivan <bryano@fb.com>
parents: 18637
diff changeset
    84
                os._exit(0)
047110c0e2a8 worker: allow a function to be run in multiple worker processes
Bryan O'Sullivan <bryano@fb.com>
parents: 18637
diff changeset
    85
            except KeyboardInterrupt:
047110c0e2a8 worker: allow a function to be run in multiple worker processes
Bryan O'Sullivan <bryano@fb.com>
parents: 18637
diff changeset
    86
                os._exit(255)
19408
c7ec39c1a381 worker: properly report errors from worker processes (issue3982)
Matt Mackall <mpm@selenic.com>
parents: 19406
diff changeset
    87
                # other exceptions are allowed to propagate, we rely
c7ec39c1a381 worker: properly report errors from worker processes (issue3982)
Matt Mackall <mpm@selenic.com>
parents: 19406
diff changeset
    88
                # on lock.py's pid checks to avoid release callbacks
18709
9955fc5ee24b worker: handle worker failures more aggressively
Bryan O'Sullivan <bryano@fb.com>
parents: 18708
diff changeset
    89
        pids.append(pid)
9955fc5ee24b worker: handle worker failures more aggressively
Bryan O'Sullivan <bryano@fb.com>
parents: 18708
diff changeset
    90
    pids.reverse()
18638
047110c0e2a8 worker: allow a function to be run in multiple worker processes
Bryan O'Sullivan <bryano@fb.com>
parents: 18637
diff changeset
    91
    os.close(wfd)
047110c0e2a8 worker: allow a function to be run in multiple worker processes
Bryan O'Sullivan <bryano@fb.com>
parents: 18637
diff changeset
    92
    fp = os.fdopen(rfd, 'rb', 0)
18709
9955fc5ee24b worker: handle worker failures more aggressively
Bryan O'Sullivan <bryano@fb.com>
parents: 18708
diff changeset
    93
    def killworkers():
9955fc5ee24b worker: handle worker failures more aggressively
Bryan O'Sullivan <bryano@fb.com>
parents: 18708
diff changeset
    94
        # if one worker bails, there's no good reason to wait for the rest
9955fc5ee24b worker: handle worker failures more aggressively
Bryan O'Sullivan <bryano@fb.com>
parents: 18708
diff changeset
    95
        for p in pids:
9955fc5ee24b worker: handle worker failures more aggressively
Bryan O'Sullivan <bryano@fb.com>
parents: 18708
diff changeset
    96
            try:
9955fc5ee24b worker: handle worker failures more aggressively
Bryan O'Sullivan <bryano@fb.com>
parents: 18708
diff changeset
    97
                os.kill(p, signal.SIGTERM)
25660
328739ea70c3 global: mass rewrite to use modern exception syntax
Gregory Szorc <gregory.szorc@gmail.com>
parents: 22199
diff changeset
    98
            except OSError as err:
18709
9955fc5ee24b worker: handle worker failures more aggressively
Bryan O'Sullivan <bryano@fb.com>
parents: 18708
diff changeset
    99
                if err.errno != errno.ESRCH:
9955fc5ee24b worker: handle worker failures more aggressively
Bryan O'Sullivan <bryano@fb.com>
parents: 18708
diff changeset
   100
                    raise
9955fc5ee24b worker: handle worker failures more aggressively
Bryan O'Sullivan <bryano@fb.com>
parents: 18708
diff changeset
   101
    def waitforworkers():
22199
b3e51675f98e cleanup: avoid _ for local unused tmp variables - that is reserved for i18n
Mads Kiilerich <madski@unity3d.com>
parents: 20034
diff changeset
   102
        for _pid in pids:
18709
9955fc5ee24b worker: handle worker failures more aggressively
Bryan O'Sullivan <bryano@fb.com>
parents: 18708
diff changeset
   103
            st = _exitstatus(os.wait()[1])
19406
3185b347ae98 worker: check problem state correctly (issue3982)
Matt Mackall <mpm@selenic.com>
parents: 18914
diff changeset
   104
            if st and not problem[0]:
18709
9955fc5ee24b worker: handle worker failures more aggressively
Bryan O'Sullivan <bryano@fb.com>
parents: 18708
diff changeset
   105
                problem[0] = st
9955fc5ee24b worker: handle worker failures more aggressively
Bryan O'Sullivan <bryano@fb.com>
parents: 18708
diff changeset
   106
                killworkers()
9955fc5ee24b worker: handle worker failures more aggressively
Bryan O'Sullivan <bryano@fb.com>
parents: 18708
diff changeset
   107
    t = threading.Thread(target=waitforworkers)
9955fc5ee24b worker: handle worker failures more aggressively
Bryan O'Sullivan <bryano@fb.com>
parents: 18708
diff changeset
   108
    t.start()
18638
047110c0e2a8 worker: allow a function to be run in multiple worker processes
Bryan O'Sullivan <bryano@fb.com>
parents: 18637
diff changeset
   109
    def cleanup():
047110c0e2a8 worker: allow a function to be run in multiple worker processes
Bryan O'Sullivan <bryano@fb.com>
parents: 18637
diff changeset
   110
        signal.signal(signal.SIGINT, oldhandler)
18709
9955fc5ee24b worker: handle worker failures more aggressively
Bryan O'Sullivan <bryano@fb.com>
parents: 18708
diff changeset
   111
        t.join()
9955fc5ee24b worker: handle worker failures more aggressively
Bryan O'Sullivan <bryano@fb.com>
parents: 18708
diff changeset
   112
        status = problem[0]
9955fc5ee24b worker: handle worker failures more aggressively
Bryan O'Sullivan <bryano@fb.com>
parents: 18708
diff changeset
   113
        if status:
9955fc5ee24b worker: handle worker failures more aggressively
Bryan O'Sullivan <bryano@fb.com>
parents: 18708
diff changeset
   114
            if status < 0:
9955fc5ee24b worker: handle worker failures more aggressively
Bryan O'Sullivan <bryano@fb.com>
parents: 18708
diff changeset
   115
                os.kill(os.getpid(), -status)
9955fc5ee24b worker: handle worker failures more aggressively
Bryan O'Sullivan <bryano@fb.com>
parents: 18708
diff changeset
   116
            sys.exit(status)
18638
047110c0e2a8 worker: allow a function to be run in multiple worker processes
Bryan O'Sullivan <bryano@fb.com>
parents: 18637
diff changeset
   117
    try:
047110c0e2a8 worker: allow a function to be run in multiple worker processes
Bryan O'Sullivan <bryano@fb.com>
parents: 18637
diff changeset
   118
        for line in fp:
047110c0e2a8 worker: allow a function to be run in multiple worker processes
Bryan O'Sullivan <bryano@fb.com>
parents: 18637
diff changeset
   119
            l = line.split(' ', 1)
047110c0e2a8 worker: allow a function to be run in multiple worker processes
Bryan O'Sullivan <bryano@fb.com>
parents: 18637
diff changeset
   120
            yield int(l[0]), l[1][:-1]
047110c0e2a8 worker: allow a function to be run in multiple worker processes
Bryan O'Sullivan <bryano@fb.com>
parents: 18637
diff changeset
   121
    except: # re-raises
18709
9955fc5ee24b worker: handle worker failures more aggressively
Bryan O'Sullivan <bryano@fb.com>
parents: 18708
diff changeset
   122
        killworkers()
18638
047110c0e2a8 worker: allow a function to be run in multiple worker processes
Bryan O'Sullivan <bryano@fb.com>
parents: 18637
diff changeset
   123
        cleanup()
047110c0e2a8 worker: allow a function to be run in multiple worker processes
Bryan O'Sullivan <bryano@fb.com>
parents: 18637
diff changeset
   124
        raise
047110c0e2a8 worker: allow a function to be run in multiple worker processes
Bryan O'Sullivan <bryano@fb.com>
parents: 18637
diff changeset
   125
    cleanup()
047110c0e2a8 worker: allow a function to be run in multiple worker processes
Bryan O'Sullivan <bryano@fb.com>
parents: 18637
diff changeset
   126
18707
d1a2b086d058 worker: on error, exit similarly to the first failing worker
Bryan O'Sullivan <bryano@fb.com>
parents: 18638
diff changeset
   127
def _posixexitstatus(code):
d1a2b086d058 worker: on error, exit similarly to the first failing worker
Bryan O'Sullivan <bryano@fb.com>
parents: 18638
diff changeset
   128
    '''convert a posix exit status into the same form returned by
d1a2b086d058 worker: on error, exit similarly to the first failing worker
Bryan O'Sullivan <bryano@fb.com>
parents: 18638
diff changeset
   129
    os.spawnv
d1a2b086d058 worker: on error, exit similarly to the first failing worker
Bryan O'Sullivan <bryano@fb.com>
parents: 18638
diff changeset
   130
d1a2b086d058 worker: on error, exit similarly to the first failing worker
Bryan O'Sullivan <bryano@fb.com>
parents: 18638
diff changeset
   131
    returns None if the process was stopped instead of exiting'''
d1a2b086d058 worker: on error, exit similarly to the first failing worker
Bryan O'Sullivan <bryano@fb.com>
parents: 18638
diff changeset
   132
    if os.WIFEXITED(code):
d1a2b086d058 worker: on error, exit similarly to the first failing worker
Bryan O'Sullivan <bryano@fb.com>
parents: 18638
diff changeset
   133
        return os.WEXITSTATUS(code)
d1a2b086d058 worker: on error, exit similarly to the first failing worker
Bryan O'Sullivan <bryano@fb.com>
parents: 18638
diff changeset
   134
    elif os.WIFSIGNALED(code):
d1a2b086d058 worker: on error, exit similarly to the first failing worker
Bryan O'Sullivan <bryano@fb.com>
parents: 18638
diff changeset
   135
        return -os.WTERMSIG(code)
d1a2b086d058 worker: on error, exit similarly to the first failing worker
Bryan O'Sullivan <bryano@fb.com>
parents: 18638
diff changeset
   136
18638
047110c0e2a8 worker: allow a function to be run in multiple worker processes
Bryan O'Sullivan <bryano@fb.com>
parents: 18637
diff changeset
   137
if os.name != 'nt':
047110c0e2a8 worker: allow a function to be run in multiple worker processes
Bryan O'Sullivan <bryano@fb.com>
parents: 18637
diff changeset
   138
    _platformworker = _posixworker
18707
d1a2b086d058 worker: on error, exit similarly to the first failing worker
Bryan O'Sullivan <bryano@fb.com>
parents: 18638
diff changeset
   139
    _exitstatus = _posixexitstatus
18638
047110c0e2a8 worker: allow a function to be run in multiple worker processes
Bryan O'Sullivan <bryano@fb.com>
parents: 18637
diff changeset
   140
18637
ac4dbceeb14a worker: partition a list (of tasks) into equal-sized chunks
Bryan O'Sullivan <bryano@fb.com>
parents: 18636
diff changeset
   141
def partition(lst, nslices):
ac4dbceeb14a worker: partition a list (of tasks) into equal-sized chunks
Bryan O'Sullivan <bryano@fb.com>
parents: 18636
diff changeset
   142
    '''partition a list into N slices of equal size'''
ac4dbceeb14a worker: partition a list (of tasks) into equal-sized chunks
Bryan O'Sullivan <bryano@fb.com>
parents: 18636
diff changeset
   143
    n = len(lst)
ac4dbceeb14a worker: partition a list (of tasks) into equal-sized chunks
Bryan O'Sullivan <bryano@fb.com>
parents: 18636
diff changeset
   144
    chunk, slop = n / nslices, n % nslices
ac4dbceeb14a worker: partition a list (of tasks) into equal-sized chunks
Bryan O'Sullivan <bryano@fb.com>
parents: 18636
diff changeset
   145
    end = 0
ac4dbceeb14a worker: partition a list (of tasks) into equal-sized chunks
Bryan O'Sullivan <bryano@fb.com>
parents: 18636
diff changeset
   146
    for i in xrange(nslices):
ac4dbceeb14a worker: partition a list (of tasks) into equal-sized chunks
Bryan O'Sullivan <bryano@fb.com>
parents: 18636
diff changeset
   147
        start = end
ac4dbceeb14a worker: partition a list (of tasks) into equal-sized chunks
Bryan O'Sullivan <bryano@fb.com>
parents: 18636
diff changeset
   148
        end = start + chunk
ac4dbceeb14a worker: partition a list (of tasks) into equal-sized chunks
Bryan O'Sullivan <bryano@fb.com>
parents: 18636
diff changeset
   149
        if slop:
ac4dbceeb14a worker: partition a list (of tasks) into equal-sized chunks
Bryan O'Sullivan <bryano@fb.com>
parents: 18636
diff changeset
   150
            end += 1
ac4dbceeb14a worker: partition a list (of tasks) into equal-sized chunks
Bryan O'Sullivan <bryano@fb.com>
parents: 18636
diff changeset
   151
            slop -= 1
ac4dbceeb14a worker: partition a list (of tasks) into equal-sized chunks
Bryan O'Sullivan <bryano@fb.com>
parents: 18636
diff changeset
   152
        yield lst[start:end]