comparison mercurial/localrepo.py @ 40745:300f8564220f

tags: cache `repo.changelog` access when checking tags nodes

The tags reading process checks if the nodes referenced in tags exist. Caching
the access to `repo.changelog` provides a large speedup for repositories with
many tags.

running `hg perftags` in a large private repository
before: ! wall 0.393464 comb 0.390000 user 0.330000 sys 0.060000 (median of 25)
after:  ! wall 0.267711 comb 0.270000 user 0.210000 sys 0.060000 (median of 38)

40744:594e84a2e574

        t = {}
        if self.changelog.filteredrevs:
            tags, tt = self._findtags()
        else:
            tags = self._tagscache.tags
        for k, v in tags.iteritems():
            try:
                # ignore tags to unknown nodes
                self.changelog.rev(v)
                t[k] = v
            except (error.LookupError, ValueError):
                pass
        return t

40745:300f8564220f

        t = {}
        if self.changelog.filteredrevs:
            tags, tt = self._findtags()
        else:
            tags = self._tagscache.tags
        rev = self.changelog.rev
        for k, v in tags.iteritems():
            try:
                # ignore tags to unknown nodes
                rev(v)
                t[k] = v
            except (error.LookupError, ValueError):
                pass
        return t