Mercurial > hg-stable
view contrib/bdiff-torture.py @ 47346:f27f2afb15da
dirstate-tree: Skip readdir() in `hg status -mard`
When running the status algorithm in a mode where we don’t list unknown
or ignored files, all we care about are files that are listed in the dirstate.
We can there for skip making expensive calls to readdir() to list the contents
of filesystem directories, and instead only run stat() to get the filesystem
state of files listed in the dirstate. (This state may be an error for files
that don’t exist anymore on the filesystem.)
On 16 CPU threads, this reduces the time spent in the `status()` function for
`hg status -mard` on an old snapshot of mozilla-central from ~70ms to ~50ms.
Differential Revision: https://phab.mercurial-scm.org/D10752
author | Simon Sapin <simon.sapin@octobus.net> |
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date | Wed, 19 May 2021 16:18:16 +0200 |
parents | 2372284d9457 |
children | 6000f5b25c9b |
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# Randomized torture test generation for bdiff from __future__ import absolute_import, print_function import random import sys from mercurial import ( mdiff, pycompat, ) def reducetest(a, b): tries = 0 reductions = 0 print("reducing...") while tries < 1000: a2 = ( "\n".join(l for l in a.splitlines() if random.randint(0, 100) > 0) + "\n" ) b2 = ( "\n".join(l for l in b.splitlines() if random.randint(0, 100) > 0) + "\n" ) if a2 == a and b2 == b: continue if a2 == b2: continue tries += 1 try: test1(a, b) except Exception: reductions += 1 tries = 0 a = a2 b = b2 print("reduced:", reductions, len(a) + len(b), repr(a), repr(b)) try: test1(a, b) except Exception as inst: print("failed:", inst) sys.exit(0) def test1(a, b): d = mdiff.textdiff(a, b) if not d: raise ValueError("empty") c = mdiff.patches(a, [d]) if c != b: raise ValueError("bad") def testwrap(a, b): try: test1(a, b) return except Exception as inst: print("exception:", inst) reducetest(a, b) def test(a, b): testwrap(a, b) testwrap(b, a) def rndtest(size, noise): a = [] src = " aaaaaaaabbbbccd" for x in pycompat.xrange(size): a.append(src[random.randint(0, len(src) - 1)]) while True: b = [c for c in a if random.randint(0, 99) > noise] b2 = [] for c in b: b2.append(c) while random.randint(0, 99) < noise: b2.append(src[random.randint(0, len(src) - 1)]) if b2 != a: break a = "\n".join(a) + "\n" b = "\n".join(b2) + "\n" test(a, b) maxvol = 10000 startsize = 2 while True: size = startsize count = 0 while size < maxvol: print(size) volume = 0 while volume < maxvol: rndtest(size, 2) volume += size count += 2 size *= 2 maxvol *= 4 startsize *= 4