Mercurial > hg
view tests/test-pathencode.py @ 41247:a89b20a49c13
rust-cpython: using MissingAncestors from Python code
As precedently done with LazyAncestors on cpython.rs, we test for the
presence of the 'rustext' module.
incrementalmissingrevs() has two callers within the Mercurial core:
`setdiscovery.partialdiscovery` and the `only()` revset.
This move shows a significant discovery performance improvement
in cases where the baseline is slow: using perfdiscovery on the PyPy
repos, prepared with `contrib/discovery-helper <repo> 50 100`, we
get averaged medians of 403ms with the Rust version vs 742ms without
(about 45% better).
But there are still indications that performance can be worse in cases
the baseline is fast, possibly due to the conversion from Python to
Rust and back becoming the bottleneck. We could measure this on
mozilla-central in cases were the delta is just a few changesets.
This requires confirmation, but if that's the reason, then an
upcoming `partialdiscovery` fully in Rust should solve the problem.
Differential Revision: https://phab.mercurial-scm.org/D5551
author | Georges Racinet <georges.racinet@octobus.net> |
---|---|
date | Fri, 30 Nov 2018 14:35:57 +0100 |
parents | 1b230e19d044 |
children | 2372284d9457 |
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# This is a randomized test that generates different pathnames every # time it is invoked, and tests the encoding of those pathnames. # # It uses a simple probabilistic model to generate valid pathnames # that have proven likely to expose bugs and divergent behavior in # different encoding implementations. from __future__ import absolute_import, print_function import binascii import collections import itertools import math import os import random import sys import time from mercurial import ( pycompat, store, ) try: xrange except NameError: xrange = range validchars = set(map(pycompat.bytechr, range(0, 256))) alphanum = range(ord('A'), ord('Z')) for c in (b'\0', b'/'): validchars.remove(c) winreserved = (b'aux con prn nul'.split() + [b'com%d' % i for i in xrange(1, 10)] + [b'lpt%d' % i for i in xrange(1, 10)]) def casecombinations(names): '''Build all case-diddled combinations of names.''' combos = set() for r in names: for i in xrange(len(r) + 1): for c in itertools.combinations(xrange(len(r)), i): d = r for j in c: d = b''.join((d[:j], d[j:j + 1].upper(), d[j + 1:])) combos.add(d) return sorted(combos) def buildprobtable(fp, cmd='hg manifest tip'): '''Construct and print a table of probabilities for path name components. The numbers are percentages.''' counts = collections.defaultdict(lambda: 0) for line in os.popen(cmd).read().splitlines(): if line[-2:] in ('.i', '.d'): line = line[:-2] if line.startswith('data/'): line = line[5:] for c in line: counts[c] += 1 for c in '\r/\n': counts.pop(c, None) t = sum(counts.itervalues()) / 100.0 fp.write('probtable = (') for i, (k, v) in enumerate(sorted(counts.items(), key=lambda x: x[1], reverse=True)): if (i % 5) == 0: fp.write('\n ') vt = v / t if vt < 0.0005: break fp.write('(%r, %.03f), ' % (k, vt)) fp.write('\n )\n') # A table of character frequencies (as percentages), gleaned by # looking at filelog names from a real-world, very large repo. probtable = ( (b't', 9.828), (b'e', 9.042), (b's', 8.011), (b'a', 6.801), (b'i', 6.618), (b'g', 5.053), (b'r', 5.030), (b'o', 4.887), (b'p', 4.363), (b'n', 4.258), (b'l', 3.830), (b'h', 3.693), (b'_', 3.659), (b'.', 3.377), (b'm', 3.194), (b'u', 2.364), (b'd', 2.296), (b'c', 2.163), (b'b', 1.739), (b'f', 1.625), (b'6', 0.666), (b'j', 0.610), (b'y', 0.554), (b'x', 0.487), (b'w', 0.477), (b'k', 0.476), (b'v', 0.473), (b'3', 0.336), (b'1', 0.335), (b'2', 0.326), (b'4', 0.310), (b'5', 0.305), (b'9', 0.302), (b'8', 0.300), (b'7', 0.299), (b'q', 0.298), (b'0', 0.250), (b'z', 0.223), (b'-', 0.118), (b'C', 0.095), (b'T', 0.087), (b'F', 0.085), (b'B', 0.077), (b'S', 0.076), (b'P', 0.076), (b'L', 0.059), (b'A', 0.058), (b'N', 0.051), (b'D', 0.049), (b'M', 0.046), (b'E', 0.039), (b'I', 0.035), (b'R', 0.035), (b'G', 0.028), (b'U', 0.026), (b'W', 0.025), (b'O', 0.017), (b'V', 0.015), (b'H', 0.013), (b'Q', 0.011), (b'J', 0.007), (b'K', 0.005), (b'+', 0.004), (b'X', 0.003), (b'Y', 0.001), ) for c, _ in probtable: validchars.remove(c) validchars = list(validchars) def pickfrom(rng, table): c = 0 r = rng.random() * sum(i[1] for i in table) for i, p in table: c += p if c >= r: return i reservedcombos = casecombinations(winreserved) # The first component of a name following a slash. firsttable = ( (lambda rng: pickfrom(rng, probtable), 90), (lambda rng: rng.choice(validchars), 5), (lambda rng: rng.choice(reservedcombos), 5), ) # Components of a name following the first. resttable = firsttable[:-1] # Special suffixes. internalsuffixcombos = casecombinations(b'.hg .i .d'.split()) # The last component of a path, before a slash or at the end of a name. lasttable = resttable + ( (lambda rng: b'', 95), (lambda rng: rng.choice(internalsuffixcombos), 5), ) def makepart(rng, k): '''Construct a part of a pathname, without slashes.''' p = pickfrom(rng, firsttable)(rng) l = len(p) ps = [p] maxl = rng.randint(1, k) while l < maxl: p = pickfrom(rng, resttable)(rng) l += len(p) ps.append(p) ps.append(pickfrom(rng, lasttable)(rng)) return b''.join(ps) def makepath(rng, j, k): '''Construct a complete pathname.''' return (b'data/' + b'/'.join(makepart(rng, k) for _ in xrange(j)) + rng.choice([b'.d', b'.i'])) def genpath(rng, count): '''Generate random pathnames with gradually increasing lengths.''' mink, maxk = 1, 4096 def steps(): for i in xrange(count): yield mink + int(round(math.sqrt((maxk - mink) * float(i) / count))) for k in steps(): x = rng.randint(1, k) y = rng.randint(1, k) yield makepath(rng, x, y) def runtests(rng, seed, count): nerrs = 0 for p in genpath(rng, count): h = store._pathencode(p) # uses C implementation, if available r = store._hybridencode(p, True) # reference implementation in Python if h != r: if nerrs == 0: print('seed:', hex(seed)[:-1], file=sys.stderr) print("\np: '%s'" % p.encode("string_escape"), file=sys.stderr) print("h: '%s'" % h.encode("string_escape"), file=sys.stderr) print("r: '%s'" % r.encode("string_escape"), file=sys.stderr) nerrs += 1 return nerrs def main(): import getopt # Empirically observed to take about a second to run count = 100 seed = None opts, args = getopt.getopt(sys.argv[1:], 'c:s:', ['build', 'count=', 'seed=']) for o, a in opts: if o in ('-c', '--count'): count = int(a) elif o in ('-s', '--seed'): seed = int(a, base=0) # accepts base 10 or 16 strings elif o == '--build': buildprobtable(sys.stdout, 'find .hg/store/data -type f && ' 'cat .hg/store/fncache 2>/dev/null') sys.exit(0) if seed is None: try: seed = int(binascii.hexlify(os.urandom(16)), 16) except AttributeError: seed = int(time.time() * 1000) rng = random.Random(seed) if runtests(rng, seed, count): sys.exit(1) if __name__ == '__main__': main()