Mercurial > hg
view mercurial/worker.py @ 31769:594dd384803c
test-serve: make the 'listening at *' lines optional
The daemonized serve process doesn't print these lines out (see 448d0c452140).
I was able to get it to with the following hack:
diff --git a/mercurial/win32.py b/mercurial/win32.py
--- a/mercurial/win32.py
+++ b/mercurial/win32.py
@@ -418,6 +418,11 @@
return str(ppid)
def spawndetached(args):
+
+ import subprocess
+ return subprocess.Popen(args, cwd=pycompat.getcwd(), env=encoding.environ,
+ creationflags=subprocess.CREATE_NEW_PROCESS_GROUP).pid
+
# No standard library function really spawns a fully detached
# process under win32 because they allocate pipes or other objects
# to handle standard streams communications. Passing these objects
However, MSYS translates --prefixes starting with '/' to 'C:/MinGW/msys/1.0',
which changes the output. The output isn't so important that I want to spend a
bunch of time on this, and risk breaking some subtle behavior of `hg serve -d`
with the more complicated code.
author | Matt Harbison <matt_harbison@yahoo.com> |
---|---|
date | Sun, 02 Apr 2017 00:56:52 -0400 |
parents | 9d3d56aa1a9f |
children | 8f8ad0139b8b |
line wrap: on
line source
# worker.py - master-slave parallelism support # # Copyright 2013 Facebook, Inc. # # This software may be used and distributed according to the terms of the # GNU General Public License version 2 or any later version. from __future__ import absolute_import import errno import os import signal import sys from .i18n import _ from . import ( encoding, error, pycompat, scmutil, util, ) def countcpus(): '''try to count the number of CPUs on the system''' # posix try: n = int(os.sysconf('SC_NPROCESSORS_ONLN')) if n > 0: return n except (AttributeError, ValueError): pass # windows try: n = int(encoding.environ['NUMBER_OF_PROCESSORS']) if n > 0: return n except (KeyError, ValueError): pass return 1 def _numworkers(ui): s = ui.config('worker', 'numcpus') if s: try: n = int(s) if n >= 1: return n except ValueError: raise error.Abort(_('number of cpus must be an integer')) return min(max(countcpus(), 4), 32) if pycompat.osname == 'posix': _startupcost = 0.01 else: _startupcost = 1e30 def worthwhile(ui, costperop, nops): '''try to determine whether the benefit of multiple processes can outweigh the cost of starting them''' linear = costperop * nops workers = _numworkers(ui) benefit = linear - (_startupcost * workers + linear / workers) return benefit >= 0.15 def worker(ui, costperarg, func, staticargs, args): '''run a function, possibly in parallel in multiple worker processes. returns a progress iterator costperarg - cost of a single task func - function to run staticargs - arguments to pass to every invocation of the function args - arguments to split into chunks, to pass to individual workers ''' if worthwhile(ui, costperarg, len(args)): return _platformworker(ui, func, staticargs, args) return func(*staticargs + (args,)) def _posixworker(ui, func, staticargs, args): rfd, wfd = os.pipe() workers = _numworkers(ui) oldhandler = signal.getsignal(signal.SIGINT) signal.signal(signal.SIGINT, signal.SIG_IGN) pids, problem = set(), [0] def killworkers(): # unregister SIGCHLD handler as all children will be killed. This # function shouldn't be interrupted by another SIGCHLD; otherwise pids # could be updated while iterating, which would cause inconsistency. signal.signal(signal.SIGCHLD, oldchldhandler) # if one worker bails, there's no good reason to wait for the rest for p in pids: try: os.kill(p, signal.SIGTERM) except OSError as err: if err.errno != errno.ESRCH: raise def waitforworkers(blocking=True): for pid in pids.copy(): p = st = 0 while True: try: p, st = os.waitpid(pid, (0 if blocking else os.WNOHANG)) break except OSError as e: if e.errno == errno.EINTR: continue elif e.errno == errno.ECHILD: # child would already be reaped, but pids yet been # updated (maybe interrupted just after waitpid) pids.discard(pid) break else: raise if not p: # skip subsequent steps, because child process should # be still running in this case continue pids.discard(p) st = _exitstatus(st) if st and not problem[0]: problem[0] = st def sigchldhandler(signum, frame): waitforworkers(blocking=False) if problem[0]: killworkers() oldchldhandler = signal.signal(signal.SIGCHLD, sigchldhandler) ui.flush() for pargs in partition(args, workers): pid = os.fork() if pid == 0: signal.signal(signal.SIGINT, oldhandler) signal.signal(signal.SIGCHLD, oldchldhandler) def workerfunc(): os.close(rfd) for i, item in func(*(staticargs + (pargs,))): os.write(wfd, '%d %s\n' % (i, item)) # make sure we use os._exit in all code paths. otherwise the worker # may do some clean-ups which could cause surprises like deadlock. # see sshpeer.cleanup for example. try: try: scmutil.callcatch(ui, workerfunc) finally: ui.flush() except KeyboardInterrupt: os._exit(255) except: # never return, therefore no re-raises try: ui.traceback() ui.flush() finally: os._exit(255) else: os._exit(0) pids.add(pid) os.close(wfd) fp = os.fdopen(rfd, pycompat.sysstr('rb'), 0) def cleanup(): signal.signal(signal.SIGINT, oldhandler) waitforworkers() signal.signal(signal.SIGCHLD, oldchldhandler) status = problem[0] if status: if status < 0: os.kill(os.getpid(), -status) sys.exit(status) try: for line in util.iterfile(fp): l = line.split(' ', 1) yield int(l[0]), l[1][:-1] except: # re-raises killworkers() cleanup() raise cleanup() def _posixexitstatus(code): '''convert a posix exit status into the same form returned by os.spawnv returns None if the process was stopped instead of exiting''' if os.WIFEXITED(code): return os.WEXITSTATUS(code) elif os.WIFSIGNALED(code): return -os.WTERMSIG(code) if pycompat.osname != 'nt': _platformworker = _posixworker _exitstatus = _posixexitstatus def partition(lst, nslices): '''partition a list into N slices of roughly equal size The current strategy takes every Nth element from the input. If we ever write workers that need to preserve grouping in input we should consider allowing callers to specify a partition strategy. mpm is not a fan of this partitioning strategy when files are involved. In his words: Single-threaded Mercurial makes a point of creating and visiting files in a fixed order (alphabetical). When creating files in order, a typical filesystem is likely to allocate them on nearby regions on disk. Thus, when revisiting in the same order, locality is maximized and various forms of OS and disk-level caching and read-ahead get a chance to work. This effect can be quite significant on spinning disks. I discovered it circa Mercurial v0.4 when revlogs were named by hashes of filenames. Tarring a repo and copying it to another disk effectively randomized the revlog ordering on disk by sorting the revlogs by hash and suddenly performance of my kernel checkout benchmark dropped by ~10x because the "working set" of sectors visited no longer fit in the drive's cache and the workload switched from streaming to random I/O. What we should really be doing is have workers read filenames from a ordered queue. This preserves locality and also keeps any worker from getting more than one file out of balance. ''' for i in range(nslices): yield lst[i::nslices]