Mercurial > public > mercurial-scm > hg-stable
diff mercurial/revlog.py @ 16414:e8d37b78acfb
parsers: use base-16 trie for faster node->rev mapping
This greatly speeds up node->rev lookups, with results that are
often user-perceptible: for instance, "hg --time log" of the node
associated with rev 1000 on a linux-2.6 repo improves from 0.3
seconds to 0.03. I have not found any instances of slowdowns.
The new perfnodelookup command in contrib/perf.py demonstrates the
speedup more dramatically, since it performs no I/O. For a single
lookup, the new code is about 40x faster.
These changes also prepare the ground for the possibility of further
improving the performance of prefix-based node lookups.
author | Bryan O'Sullivan <bryano@fb.com> |
---|---|
date | Thu, 12 Apr 2012 14:05:59 -0700 |
parents | d7d64b89a65c |
children | e5750c6716eb |
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--- a/mercurial/revlog.py Thu Apr 12 20:22:18 2012 -0500 +++ b/mercurial/revlog.py Thu Apr 12 14:05:59 2012 -0700 @@ -174,7 +174,7 @@ def parseindex(self, data, inline): # call the C implementation to parse the index data index, cache = parsers.parse_index2(data, inline) - return index, None, cache + return index, getattr(index, 'nodemap', None), cache def packentry(self, entry, node, version, rev): p = _pack(indexformatng, *entry) @@ -295,10 +295,21 @@ except KeyError: return False + def clearcaches(self): + try: + self._nodecache.clearcaches() + except AttributeError: + self._nodecache = {nullid: nullrev} + self._nodepos = None + def rev(self, node): try: return self._nodecache[node] + except RevlogError: + # parsers.c radix tree lookup failed + raise LookupError(node, self.indexfile, _('no node')) except KeyError: + # pure python cache lookup failed n = self._nodecache i = self.index p = self._nodepos