transaction: open a file with checkambig=True to avoid file stat ambiguity
Before this patch, if steps below occurs at "the same time in sec",
all of mtime, ctime and size are same between (1) and (3).
1. append data to revlog-style file (and close transaction)
2. discard appended data by truncation of rollback
3. append same size but different data to revlog-style file again
Therefore, cache validation doesn't work after (3) as expected.
To avoid file stat ambiguity around truncation, this patch opens a
file with checkambig=True.
This is a part of ExactCacheValidationPlan.
https://www.mercurial-scm.org/wiki/ExactCacheValidationPlan
#!/usr/bin/env python
#
# hgperf - measure performance of Mercurial commands
#
# Copyright 2014 Matt Mackall <mpm@selenic.com>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
'''measure performance of Mercurial commands
Using ``hgperf`` instead of ``hg`` measures performance of the target
Mercurial command. For example, the execution below measures
performance of :hg:`heads --topo`::
$ hgperf heads --topo
All command output via ``ui`` is suppressed, and just measurement
result is displayed: see also "perf" extension in "contrib".
Costs of processing before dispatching to the command function like
below are not measured::
- parsing command line (e.g. option validity check)
- reading configuration files in
But ``pre-`` and ``post-`` hook invocation for the target command is
measured, even though these are invoked before or after dispatching to
the command function, because these may be required to repeat
execution of the target command correctly.
'''
import os
import sys
libdir = '@LIBDIR@'
if libdir != '@' 'LIBDIR' '@':
if not os.path.isabs(libdir):
libdir = os.path.join(os.path.dirname(os.path.realpath(__file__)),
libdir)
libdir = os.path.abspath(libdir)
sys.path.insert(0, libdir)
# enable importing on demand to reduce startup time
try:
from mercurial import demandimport; demandimport.enable()
except ImportError:
import sys
sys.stderr.write("abort: couldn't find mercurial libraries in [%s]\n" %
' '.join(sys.path))
sys.stderr.write("(check your install and PYTHONPATH)\n")
sys.exit(-1)
import mercurial.util
import mercurial.dispatch
import time
def timer(func, title=None):
results = []
begin = time.time()
count = 0
while True:
ostart = os.times()
cstart = time.time()
r = func()
cstop = time.time()
ostop = os.times()
count += 1
a, b = ostart, ostop
results.append((cstop - cstart, b[0] - a[0], b[1]-a[1]))
if cstop - begin > 3 and count >= 100:
break
if cstop - begin > 10 and count >= 3:
break
if title:
sys.stderr.write("! %s\n" % title)
if r:
sys.stderr.write("! result: %s\n" % r)
m = min(results)
sys.stderr.write("! wall %f comb %f user %f sys %f (best of %d)\n"
% (m[0], m[1] + m[2], m[1], m[2], count))
orgruncommand = mercurial.dispatch.runcommand
def runcommand(lui, repo, cmd, fullargs, ui, options, d, cmdpats, cmdoptions):
ui.pushbuffer()
lui.pushbuffer()
timer(lambda : orgruncommand(lui, repo, cmd, fullargs, ui,
options, d, cmdpats, cmdoptions))
ui.popbuffer()
lui.popbuffer()
mercurial.dispatch.runcommand = runcommand
for fp in (sys.stdin, sys.stdout, sys.stderr):
mercurial.util.setbinary(fp)
mercurial.dispatch.run()