Mercurial > hg
view mercurial/filelog.py @ 20713:6a1a4c212d50
revset: improve head revset performance
Previously the head() revset would iterate over every item in the subset and
check if it was a head. Since the subset is often the entire repo, this was
slow on large repos. Now we iterate over each item in the head list and check if
it's in the subset, which results in much less work.
hg log -r 'head()' on a large repo:
Before: 0.95s
After: 0.28s
author | Durham Goode <durham@fb.com> |
---|---|
date | Thu, 13 Mar 2014 13:47:21 -0700 |
parents | 3bda242bf244 |
children | 4669e26747c3 |
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# filelog.py - file history class for mercurial # # Copyright 2005-2007 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. import revlog import re _mdre = re.compile('\1\n') def _parsemeta(text): """return (metadatadict, keylist, metadatasize)""" # text can be buffer, so we can't use .startswith or .index if text[:2] != '\1\n': return None, None, None s = _mdre.search(text, 2).start() mtext = text[2:s] meta = {} keys = [] for l in mtext.splitlines(): k, v = l.split(": ", 1) meta[k] = v keys.append(k) return meta, keys, (s + 2) def _packmeta(meta, keys=None): if not keys: keys = sorted(meta.iterkeys()) return "".join("%s: %s\n" % (k, meta[k]) for k in keys) class filelog(revlog.revlog): def __init__(self, opener, path): super(filelog, self).__init__(opener, "/".join(("data", path + ".i"))) def read(self, node): t = self.revision(node) if not t.startswith('\1\n'): return t s = t.index('\1\n', 2) return t[s + 2:] def add(self, text, meta, transaction, link, p1=None, p2=None): if meta or text.startswith('\1\n'): text = "\1\n%s\1\n%s" % (_packmeta(meta), text) return self.addrevision(text, transaction, link, p1, p2) def renamed(self, node): if self.parents(node)[0] != revlog.nullid: return False t = self.revision(node) m = _parsemeta(t)[0] if m and "copy" in m: return (m["copy"], revlog.bin(m["copyrev"])) return False def size(self, rev): """return the size of a given revision""" # for revisions with renames, we have to go the slow way node = self.node(rev) if self.renamed(node): return len(self.read(node)) # XXX if self.read(node).startswith("\1\n"), this returns (size+4) return super(filelog, self).size(rev) def cmp(self, node, text): """compare text with a given file revision returns True if text is different than what is stored. """ t = text if text.startswith('\1\n'): t = '\1\n\1\n' + text samehashes = not super(filelog, self).cmp(node, t) if samehashes: return False # renaming a file produces a different hash, even if the data # remains unchanged. Check if it's the case (slow): if self.renamed(node): t2 = self.read(node) return t2 != text return True def _file(self, f): return filelog(self.opener, f)