Mercurial > hg-stable
view tests/killdaemons.py @ 32200:4d504e541d3d
rebase: use matcher to optimize manifestmerge
The old merge code would call manifestmerge and calculate the complete diff
between the source to the destination. In many cases, like rebase, the vast
majority of differences between the source and destination are irrelevant
because they are differences between the destination and the common ancestor
only, and therefore don't affect the merge. Since most actions are 'keep', all
the effort to compute them is wasted.
Instead, let's compute the difference between the source and the common ancestor
and only perform the diff of those files against the merge destination. When
using treemanifest, this lets us avoid loading almost the entire tree when
rebasing from a very old ancestor. This speeds up rebase of an old stack of 27
commits by 20x.
In mozilla-central, without treemanifest, when rebasing a commit from
default~100000 to default, this speeds up the manifestmerge step from 2.6s to
1.2s. However, the additional diff adds an overhead to all manifestmerge calls,
especially for flat manifests. When rebasing a commit from default~1 to default
it appears to add 100ms in mozilla-central. While we could put this optimization
behind a flag, I think the fact that it makes merge O(number of changes being
applied) instead of O(number of changes between X and Y) justifies it.
author | Durham Goode <durham@fb.com> |
---|---|
date | Wed, 03 May 2017 10:43:59 -0700 |
parents | 4ddfb730789d |
children | f840b2621cce |
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#!/usr/bin/env python from __future__ import absolute_import import errno import os import signal import sys import time if os.name =='nt': import ctypes def _check(ret, expectederr=None): if ret == 0: winerrno = ctypes.GetLastError() if winerrno == expectederr: return True raise ctypes.WinError(winerrno) def kill(pid, logfn, tryhard=True): logfn('# Killing daemon process %d' % pid) PROCESS_TERMINATE = 1 PROCESS_QUERY_INFORMATION = 0x400 SYNCHRONIZE = 0x00100000 WAIT_OBJECT_0 = 0 WAIT_TIMEOUT = 258 handle = ctypes.windll.kernel32.OpenProcess( PROCESS_TERMINATE|SYNCHRONIZE|PROCESS_QUERY_INFORMATION, False, pid) if handle == 0: _check(0, 87) # err 87 when process not found return # process not found, already finished try: r = ctypes.windll.kernel32.WaitForSingleObject(handle, 100) if r == WAIT_OBJECT_0: pass # terminated, but process handle still available elif r == WAIT_TIMEOUT: _check(ctypes.windll.kernel32.TerminateProcess(handle, -1)) else: _check(r) # TODO?: forcefully kill when timeout # and ?shorter waiting time? when tryhard==True r = ctypes.windll.kernel32.WaitForSingleObject(handle, 100) # timeout = 100 ms if r == WAIT_OBJECT_0: pass # process is terminated elif r == WAIT_TIMEOUT: logfn('# Daemon process %d is stuck') else: _check(r) # any error except: #re-raises ctypes.windll.kernel32.CloseHandle(handle) # no _check, keep error raise _check(ctypes.windll.kernel32.CloseHandle(handle)) else: def kill(pid, logfn, tryhard=True): try: os.kill(pid, 0) logfn('# Killing daemon process %d' % pid) os.kill(pid, signal.SIGTERM) if tryhard: for i in range(10): time.sleep(0.05) os.kill(pid, 0) else: time.sleep(0.1) os.kill(pid, 0) logfn('# Daemon process %d is stuck - really killing it' % pid) os.kill(pid, signal.SIGKILL) except OSError as err: if err.errno != errno.ESRCH: raise def killdaemons(pidfile, tryhard=True, remove=False, logfn=None): if not logfn: logfn = lambda s: s # Kill off any leftover daemon processes try: fp = open(pidfile) for line in fp: try: pid = int(line) if pid <= 0: raise ValueError except ValueError: logfn('# Not killing daemon process %s - invalid pid' % line.rstrip()) continue kill(pid, logfn, tryhard) fp.close() if remove: os.unlink(pidfile) except IOError: pass if __name__ == '__main__': if len(sys.argv) > 1: path, = sys.argv[1:] else: path = os.environ["DAEMON_PIDS"] killdaemons(path)