# HG changeset patch # User Boris Feld <boris.f...@octobus.net> # Date 1539125435 -7200 # Wed Oct 10 00:50:35 2018 +0200 # Node ID 63e215de867f1d39c18fbb34c47ca30827b3ae1c # Parent 16ef27511c0b9337d1b6cba011bda8b46608dcc6 # EXP-Topic copy-perf # Available At https://bitbucket.org/octobus/mercurial-devel/ # hg pull https://bitbucket.org/octobus/mercurial-devel/ -r 63e215de867f context: introduce an `isintroducedafter` method and use it in copies
Right now, copy tracing make effort to not traverse the graph too much to save performance. It uses a "limit" acting as a floor revision past which data are no longer relevant to the current copy tracing. However, to enforce this limit, it does a call to `filectx.rev()` and that call can trigger a graph traversal on its own. That extra graph traversal is unaware of the current limit and can become very expensive. That cost is increased by the nature of work done in adjust link rev, we are not only walking down the graph, we are also checking the affected file for each revision we walk through. Something significantly more expensive than the walk itself. To work around this we need to make the `filectx` operation aware of the current limit. The first step is to introduce a dedicated method: `isintroducedafter`. We'll then rework that method logic to stop traversal as soon as possible. diff --git a/mercurial/context.py b/mercurial/context.py --- a/mercurial/context.py +++ b/mercurial/context.py @@ -762,6 +762,12 @@ class basefilectx(object): # result is crash somewhere else at to some point. return lkr + def isintroducedafter(self, changelogrev): + """True if a filectx has been introduced after a given floor revision + """ + return (self.linkrev() >= changelogrev + or self.introrev() >= changelogrev) + def introrev(self): """return the rev of the changeset which introduced this file revision diff --git a/mercurial/copies.py b/mercurial/copies.py --- a/mercurial/copies.py +++ b/mercurial/copies.py @@ -139,7 +139,7 @@ def _tracefile(fctx, am, limit=-1): for f in fctx.ancestors(): if am.get(f.path(), None) == f.filenode(): return f - if limit >= 0 and f.linkrev() < limit and f.rev() < limit: + if limit >= 0 and not f.isintroducedafter(limit): return None def _dirstatecopies(d, match=None): _______________________________________________ Mercurial-devel mailing list Mercurial-devel@mercurial-scm.org https://www.mercurial-scm.org/mailman/listinfo/mercurial-devel