setdiscovery: stop limiting the number of local head we initially send
In our testing this limitation provides now real gain and instead triggers
pathological discovery timing for some repository with many heads.
See inline documentation for details.
Some timing below:
Mozilla try repository, (~1M revs, ~35K heads), discovery between 2 clones with
100 head missing on each side
before:
! wall 1.492111 comb 1.490000 user 1.450000 sys 0.040000 (best of 20)
! wall 1.813992 comb 1.820000 user 1.700000 sys 0.120000 (max of 20)
! wall 1.574326 comb 1.573500 user 1.522000 sys 0.051500 (avg of 20)
! wall 1.572583 comb 1.570000 user 1.520000 sys 0.050000 (median of 20)
after:
! wall 1.147834 comb 1.150000 user 1.090000 sys 0.060000 (best of 20)
! wall 1.449144 comb 1.450000 user 1.330000 sys 0.120000 (max of 20)
! wall 1.204618 comb 1.202500 user 1.146500 sys 0.056000 (avg of 20)
! wall 1.194407 comb 1.190000 user 1.140000 sys 0.050000 (median of 20)
pypy (~100 heads, 317 heads) discovery between clones with only 42 common heads
before:
! wall 0.031653 comb 0.030000 user 0.030000 sys 0.000000 (best of 25)
! wall 0.055719 comb 0.050000 user 0.040000 sys 0.010000 (max of 25)
! wall 0.038939 comb 0.039600 user 0.038400 sys 0.001200 (avg of 25)
! wall 0.038660 comb 0.050000 user 0.040000 sys 0.010000 (median of 25)
after:
! wall 0.018754 comb 0.020000 user 0.020000 sys 0.000000 (best of 49)
! wall 0.034505 comb 0.040000 user 0.030000 sys 0.010000 (max of 49)
! wall 0.019631 comb 0.019796 user 0.018367 sys 0.001429 (avg of 49)
! wall 0.019132 comb 0.020000 user 0.020000 sys 0.000000 (median of 49)
Private repository (~1M revs, ~3K heads), discovery from a strip subset, about
100 changesets to be pulled.
before:
! wall 1.837729 comb 1.840000 user 1.790000 sys 0.050000 (best of 20)
! wall 2.203468 comb 2.200000 user 2.100000 sys 0.100000 (max of 20)
! wall 2.049355 comb 2.048500 user 2.002500 sys 0.046000 (avg of 20)
! wall 2.035315 comb 2.040000 user 2.000000 sys 0.040000 (median of 20)
after:
! wall 0.136598 comb 0.130000 user 0.110000 sys 0.020000 (best of 20)
! wall 0.330519 comb 0.330000 user 0.260000 sys 0.070000 (max of 20)
! wall 0.157254 comb 0.155500 user 0.123000 sys 0.032500 (avg of 20)
! wall 0.149870 comb 0.140000 user 0.110000 sys 0.030000 (median of 20)
Same private repo, discovery between two clone with 500 different heads on each
side:
before:
! wall 2.372919 comb 2.370000 user 2.320000 sys 0.050000 (best of 20)
! wall 2.622422 comb 2.610000 user 2.510000 sys 0.100000 (max of 20)
! wall 2.450135 comb 2.450000 user 2.402000 sys 0.048000 (avg of 20)
! wall 2.443896 comb 2.450000 user 2.410000 sys 0.040000 (median of 20)
after:
! wall 0.625497 comb 0.620000 user 0.570000 sys 0.050000 (best of 20)
! wall 0.834723 comb 0.820000 user 0.730000 sys 0.090000 (max of 20)
! wall 0.675725 comb 0.675500 user 0.628000 sys 0.047500 (avg of 20)
! wall 0.671614 comb 0.680000 user 0.640000 sys 0.040000 (median of 20)
#!/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.
#
# You should run this from the root of your mercurial repository.
#
# call with --help for details
from __future__ import absolute_import, print_function
import math
import optparse # cannot use argparse, python 2.7 only
import os
import re
import subprocess
import sys
DEFAULTVARIANTS = ['plain', 'min', 'max', 'first', 'last',
'reverse', 'reverse+first', 'reverse+last',
'sort', 'sort+first', 'sort+last']
def check_output(*args, **kwargs):
kwargs.setdefault('stderr', subprocess.PIPE)
kwargs.setdefault('stdout', subprocess.PIPE)
proc = subprocess.Popen(*args, **kwargs)
output, error = proc.communicate()
if proc.returncode != 0:
raise subprocess.CalledProcessError(proc.returncode, ' '.join(args[0]))
return output
def update(rev):
"""update the repo to a revision"""
try:
subprocess.check_call(['hg', 'update', '--quiet', '--check', str(rev)])
check_output(['make', 'local'],
stderr=None) # suppress output except for error/warning
except subprocess.CalledProcessError as exc:
print('update to revision %s failed, aborting'%rev, file=sys.stderr)
sys.exit(exc.returncode)
def hg(cmd, repo=None):
"""run a mercurial command
<cmd> is the list of command + argument,
<repo> is an optional repository path to run this command in."""
fullcmd = ['./hg']
if repo is not None:
fullcmd += ['-R', repo]
fullcmd += ['--config',
'extensions.perf=' + os.path.join(contribdir, 'perf.py')]
fullcmd += cmd
return check_output(fullcmd, stderr=subprocess.STDOUT)
def perf(revset, target=None, contexts=False):
"""run benchmark for this very revset"""
try:
args = ['perfrevset']
if contexts:
args.append('--contexts')
args.append('--')
args.append(revset)
output = hg(args, repo=target)
return parseoutput(output)
except subprocess.CalledProcessError as exc:
print('abort: cannot run revset benchmark: %s'%exc.cmd, file=sys.stderr)
if getattr(exc, 'output', None) is None: # no output before 2.7
print('(no output)', file=sys.stderr)
else:
print(exc.output, file=sys.stderr)
return None
outputre = re.compile(br'! wall (\d+.\d+) comb (\d+.\d+) user (\d+.\d+) '
br'sys (\d+.\d+) \(best of (\d+)\)')
def parseoutput(output):
"""parse a textual output into a dict
We cannot just use json because we want to compare with old
versions of Mercurial that may not support json output.
"""
match = outputre.search(output)
if not match:
print('abort: invalid output:', file=sys.stderr)
print(output, file=sys.stderr)
sys.exit(1)
return {'comb': float(match.group(2)),
'count': int(match.group(5)),
'sys': float(match.group(3)),
'user': float(match.group(4)),
'wall': float(match.group(1)),
}
def printrevision(rev):
"""print data about a revision"""
sys.stdout.write("Revision ")
sys.stdout.flush()
subprocess.check_call(['hg', 'log', '--rev', str(rev), '--template',
'{if(tags, " ({tags})")} '
'{rev}:{node|short}: {desc|firstline}\n'])
def idxwidth(nbidx):
"""return the max width of number used for index
This is similar to log10(nbidx), but we use custom code here
because we start with zero and we'd rather not deal with all the
extra rounding business that log10 would imply.
"""
nbidx -= 1 # starts at 0
idxwidth = 0
while nbidx:
idxwidth += 1
nbidx //= 10
if not idxwidth:
idxwidth = 1
return idxwidth
def getfactor(main, other, field, sensitivity=0.05):
"""return the relative factor between values for 'field' in main and other
Return None if the factor is insignificant (less than <sensitivity>
variation)."""
factor = 1
if main is not None:
factor = other[field] / main[field]
low, high = 1 - sensitivity, 1 + sensitivity
if (low < factor < high):
return None
return factor
def formatfactor(factor):
"""format a factor into a 4 char string
22%
156%
x2.4
x23
x789
x1e4
x5x7
"""
if factor is None:
return ' '
elif factor < 2:
return '%3i%%' % (factor * 100)
elif factor < 10:
return 'x%3.1f' % factor
elif factor < 1000:
return '%4s' % ('x%i' % factor)
else:
order = int(math.log(factor)) + 1
while math.log(factor) > 1:
factor //= 0
return 'x%ix%i' % (factor, order)
def formattiming(value):
"""format a value to strictly 8 char, dropping some precision if needed"""
if value < 10**7:
return ('%.6f' % value)[:8]
else:
# value is HUGE very unlikely to happen (4+ month run)
return '%i' % value
_marker = object()
def printresult(variants, idx, data, maxidx, verbose=False, reference=_marker):
"""print a line of result to stdout"""
mask = '%%0%ii) %%s' % idxwidth(maxidx)
out = []
for var in variants:
if data[var] is None:
out.append('error ')
out.append(' ' * 4)
continue
out.append(formattiming(data[var]['wall']))
if reference is not _marker:
factor = None
if reference is not None:
factor = getfactor(reference[var], data[var], 'wall')
out.append(formatfactor(factor))
if verbose:
out.append(formattiming(data[var]['comb']))
out.append(formattiming(data[var]['user']))
out.append(formattiming(data[var]['sys']))
out.append('%6d' % data[var]['count'])
print(mask % (idx, ' '.join(out)))
def printheader(variants, maxidx, verbose=False, relative=False):
header = [' ' * (idxwidth(maxidx) + 1)]
for var in variants:
if not var:
var = 'iter'
if len(var) > 8:
var = var[:3] + '..' + var[-3:]
header.append('%-8s' % var)
if relative:
header.append(' ')
if verbose:
header.append('%-8s' % 'comb')
header.append('%-8s' % 'user')
header.append('%-8s' % 'sys')
header.append('%6s' % 'count')
print(' '.join(header))
def getrevs(spec):
"""get the list of rev matched by a revset"""
try:
out = check_output(['hg', 'log', '--template={rev}\n', '--rev', spec])
except subprocess.CalledProcessError as exc:
print("abort, can't get revision from %s"%spec, file=sys.stderr)
sys.exit(exc.returncode)
return [r for r in out.split() if r]
def applyvariants(revset, variant):
if variant == 'plain':
return revset
for var in variant.split('+'):
revset = '%s(%s)' % (var, revset)
return revset
helptext="""This script will run multiple variants of provided revsets using
different revisions in your mercurial repository. After the benchmark are run
summary output is provided. Use it to demonstrate speed improvements or pin
point regressions. Revsets to run are specified in a file (or from stdin), one
revsets per line. Line starting with '#' will be ignored, allowing insertion of
comments."""
parser = optparse.OptionParser(usage="usage: %prog [options] <revs>",
description=helptext)
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")
parser.add_option("-v", "--verbose",
action='store_true',
help="display all timing data (not just best total time)")
parser.add_option("", "--variants",
default=','.join(DEFAULTVARIANTS),
help="comma separated list of variant to test "
"(eg: plain,min,sorted) (plain = no modification)")
parser.add_option('', '--contexts',
action='store_true',
help='obtain changectx from results instead of integer revs')
(options, args) = parser.parse_args()
if not args:
parser.print_help()
sys.exit(255)
# the directory where both this script and the perf.py extension live.
contribdir = os.path.dirname(__file__)
revsetsfile = sys.stdin
if options.file:
revsetsfile = open(options.file)
revsets = [l.strip() for l in revsetsfile if not l.startswith('#')]
revsets = [l for l in revsets if l]
print("Revsets to benchmark")
print("----------------------------")
for idx, rset in enumerate(revsets):
print("%i) %s" % (idx, rset))
print("----------------------------")
print()
revs = []
for a in args:
revs.extend(getrevs(a))
variants = options.variants.split(',')
results = []
for r in revs:
print("----------------------------")
printrevision(r)
print("----------------------------")
update(r)
res = []
results.append(res)
printheader(variants, len(revsets), verbose=options.verbose)
for idx, rset in enumerate(revsets):
varres = {}
for var in variants:
varrset = applyvariants(rset, var)
data = perf(varrset, target=options.repo, contexts=options.contexts)
varres[var] = data
res.append(varres)
printresult(variants, idx, varres, len(revsets),
verbose=options.verbose)
sys.stdout.flush()
print("----------------------------")
print("""
Result by revset
================
""")
print('Revision:')
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))
printheader(variants, len(results), verbose=options.verbose, relative=True)
ref = None
for idx, data in enumerate(results):
printresult(variants, idx, data[ridx], len(results),
verbose=options.verbose, reference=ref)
ref = data[ridx]
print()