view contrib/revsetbenchmarks.py @ 24725:ee751d47cf2c

vfs: add walk

To eliminate "path prefix" (= "the root of vfs") part from "dirpath"
yielded by "os.walk()" correctly, "path prefix" should have "os.sep"
at the end of own string, but it isn't easy to ensure it, because:

  - examination by "path.endswith(os.sep)" isn't portable

    Some problematic encodings use 0x5c (= "os.sep" on Windows) as the
    tail byte of some multi-byte characters.

  - "os.path.join(path, '')" isn't portable

    With Python 2.7.9, this invocation doesn't add "os.sep" at the end
    of UNC path (see issue4557 for detail).

Python 2.7.9 changed also behavior of "os.path.normpath()" (see *) and
"os.path.splitdrive()" for UNC path.

    vfs root        normpath       splitdrive          os.sep required
    =============== ============== =================== ============
    z:\             z:\            z: + \              no
    z:\foo          z:\foo         z: + \foo           yes
    z:\foo\         z:\foo         z: + \foo           yes

    [before Python 2.7.9]
    \\foo\bar       \\foo\bar      '' + \\foo\bar      yes
    \\foo\bar\      \\foo\bar  (*) '' + \\foo\bar      yes
    \\foo\bar\baz   \\foo\bar\baz  '' + \\foo\bar\baz  yes
    \\foo\bar\baz\  \\foo\bar\baz  '' + \\foo\bar\baz  yes

    [Python 2.7.9]
    \\foo\bar       \\foo\bar      \\foo\bar + ''      yes
    \\foo\bar\      \\foo\bar\ (*) \\foo\bar + \       no
    \\foo\bar\baz   \\foo\bar\baz  \\foo\bar + \baz    yes
    \\foo\bar\baz\  \\foo\bar\baz  \\foo\bar + \baz    yes

If it is ensured that "normpath()"-ed vfs root is passed to
"splitdrive()", adding "os.sep" is required only when "path" part of
"splitdrive()" result isn't "os.sep" itself. This is just what
"pathutil.nameasprefix()" examines.

This patch applies "os.path.normpath()" on "self.join(None)"
explicitly, because it isn't ensured that vfs root is already
normalized: vfs itself is constructed with "realpath=False" (= avoid
normalizing in "vfs.__init__()") in many code paths.

This normalization should be much cheaper than subsequent file I/O for
directory traversal.

#!/usr/bin/env python

# Measure the performance of a list of revsets against multiple revisions
# defined by parameter. Checkout one by one and run perfrevset with every
# revset in the list to benchmark its performance.
#
# - First argument is a revset of mercurial own repo to runs against.
# - Second argument is the file from which the revset array will be taken
#   If second argument is omitted read it from standard input
#
# You should run this from the root of your mercurial repository.
#
# This script also does one run of the current version of mercurial installed
# to compare performance.

import sys
import os
from subprocess import check_call, Popen, CalledProcessError, STDOUT, PIPE
# cannot use argparse, python 2.7 only
from optparse import OptionParser

def check_output(*args, **kwargs):
    kwargs.setdefault('stderr', PIPE)
    kwargs.setdefault('stdout', PIPE)
    proc = Popen(*args, **kwargs)
    output, error = proc.communicate()
    if proc.returncode != 0:
        raise CalledProcessError(proc.returncode, ' '.join(args[0]))
    return output

def update(rev):
    """update the repo to a revision"""
    try:
        check_call(['hg', 'update', '--quiet', '--check', str(rev)])
    except CalledProcessError, exc:
        print >> sys.stderr, 'update to revision %s failed, aborting' % rev
        sys.exit(exc.returncode)

def perf(revset, target=None):
    """run benchmark for this very revset"""
    try:
        cmd = ['./hg',
               '--config',
               'extensions.perf='
               + os.path.join(contribdir, 'perf.py'),
               'perfrevset',
               revset]
        if target is not None:
            cmd.append('-R')
            cmd.append(target)
        output = check_output(cmd, stderr=STDOUT)
        output = output.lstrip('!') # remove useless ! in this context
        return output.strip()
    except CalledProcessError, exc:
        print >> sys.stderr, 'abort: cannot run revset benchmark'
        sys.exit(exc.returncode)

def printrevision(rev):
    """print data about a revision"""
    sys.stdout.write("Revision: ")
    sys.stdout.flush()
    check_call(['hg', 'log', '--rev', str(rev), '--template',
               '{desc|firstline}\n'])

def getrevs(spec):
    """get the list of rev matched by a revset"""
    try:
        out = check_output(['hg', 'log', '--template={rev}\n', '--rev', spec])
    except CalledProcessError, exc:
        print >> sys.stderr, "abort, can't get revision from %s" % spec
        sys.exit(exc.returncode)
    return [r for r in out.split() if r]


parser = OptionParser(usage="usage: %prog [options] <revs>")
parser.add_option("-f", "--file",
                  help="read revset from FILE (stdin if omitted)",
                  metavar="FILE")
parser.add_option("-R", "--repo",
                  help="run benchmark on REPO", metavar="REPO")

(options, args) = parser.parse_args()

if len(sys.argv) < 2:
    parser.print_help()
    sys.exit(255)

# the directory where both this script and the perf.py extension live.
contribdir = os.path.dirname(__file__)

target_rev = args[0]

revsetsfile = sys.stdin
if options.file:
    revsetsfile = open(options.file)

revsets = [l.strip() for l in revsetsfile if not l.startswith('#')]

print "Revsets to benchmark"
print "----------------------------"

for idx, rset in enumerate(revsets):
    print "%i) %s" % (idx, rset)

print "----------------------------"
print


revs = getrevs(target_rev)

results = []
for r in revs:
    print "----------------------------"
    printrevision(r)
    print "----------------------------"
    update(r)
    res = []
    results.append(res)
    for idx, rset in enumerate(revsets):
        data = perf(rset, target=options.repo)
        res.append(data)
        print "%i)" % idx, data
        sys.stdout.flush()
    print "----------------------------"


print """

Result by revset
================
"""

print 'Revision:', revs
for idx, rev in enumerate(revs):
    sys.stdout.write('%i) ' % idx)
    sys.stdout.flush()
    printrevision(rev)

print
print

for ridx, rset in enumerate(revsets):

    print "revset #%i: %s" % (ridx, rset)
    for idx, data in enumerate(results):
        print '%i) %s' % (idx, data[ridx])
    print