Mercurial > hg
view mercurial/pushkey.py @ 46020:210f9b8d7bbd stable
diff: do not concatenate immutable bytes while building a/b bodies (issue6445)
Use bytearray instead. I don't know what's changed since Python 2, but bytes
concatenation is 100x slow on Python 3.
% python2.7 -m timeit -s "s = b''" "for i in range(10000): s += b'line'"
1000 loops, best of 3: 321 usec per loop
% python3.9 -m timeit -s "s = b''" "for i in range(10000): s += b'line'"
5 loops, best of 5: 39.2 msec per loop
Benchmark using tailwind.css (measuring the fast path, a is empty):
% HGRCPATH=/dev/null python2.7 ./hg log -R /tmp/issue6445 -p --time \
--color=always --config diff.word-diff=true >/dev/null
(prev) time: real 1.580 secs (user 1.560+0.000 sys 0.020+0.000)
(this) time: real 1.610 secs (user 1.570+0.000 sys 0.030+0.000)
% HGRCPATH=/dev/null python3.9 ./hg log -R /tmp/issue6445 -p --time \
--color=always --config diff.word-diff=true >/dev/null
(prev) time: real 114.500 secs (user 114.460+0.000 sys 0.030+0.000)
(this) time: real 2.180 secs (user 2.140+0.000 sys 0.040+0.000)
Benchmark using random tabular text data (not the fast path):
% dd if=/dev/urandom bs=1k count=1000 | hexdump -v -e '16/1 "%3u," "\n"' > ttf
% hg ci -ma
% dd if=/dev/urandom bs=1k count=1000 | hexdump -v -e '16/1 "%3u," "\n"' > ttf
% hg ci -mb
% HGRCPATH=/dev/null python2.7 ./hg log -R /tmp/issue6445 -p --time \
--color=always --config diff.word-diff=true >/dev/null
(prev) time: real 3.240 secs (user 3.040+0.000 sys 0.200+0.000
(this) time: real 3.230 secs (user 3.070+0.000 sys 0.160+0.000)
% HGRCPATH=/dev/null python3.9 ./hg log -R /tmp/issue6445 -p --time \
--color=always --config diff.word-diff=true >/dev/null
(prev) time: real 44.130 secs (user 43.850+0.000 sys 0.270+0.000)
(this) time: real 4.170 secs (user 3.850+0.000 sys 0.310+0.000)
author | Yuya Nishihara <yuya@tcha.org> |
---|---|
date | Sat, 28 Nov 2020 11:15:54 +0900 |
parents | 687b865b95ad |
children | d4ba4d51f85f |
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# pushkey.py - dispatching for pushing and pulling keys # # Copyright 2010 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. from __future__ import absolute_import from . import ( bookmarks, encoding, obsolete, phases, ) def _nslist(repo): n = {} for k in _namespaces: n[k] = b"" if not obsolete.isenabled(repo, obsolete.exchangeopt): n.pop(b'obsolete') return n _namespaces = { b"namespaces": (lambda *x: False, _nslist), b"bookmarks": (bookmarks.pushbookmark, bookmarks.listbookmarks), b"phases": (phases.pushphase, phases.listphases), b"obsolete": (obsolete.pushmarker, obsolete.listmarkers), } def register(namespace, pushkey, listkeys): _namespaces[namespace] = (pushkey, listkeys) def _get(namespace): return _namespaces.get(namespace, (lambda *x: False, lambda *x: {})) def push(repo, namespace, key, old, new): '''should succeed iff value was old''' pk = _get(namespace)[0] return pk(repo, key, old, new) def list(repo, namespace): '''return a dict''' lk = _get(namespace)[1] return lk(repo) encode = encoding.fromlocal decode = encoding.tolocal def encodekeys(keys): """encode the content of a pushkey namespace for exchange over the wire""" return b'\n'.join([b'%s\t%s' % (encode(k), encode(v)) for k, v in keys]) def decodekeys(data): """decode the content of a pushkey namespace from exchange over the wire""" result = {} for l in data.splitlines(): k, v = l.split(b'\t') result[decode(k)] = decode(v) return result