Mercurial > hg
view mercurial/dirstateguard.py @ 31397:8f5ed8fa39f8
perf: perform a garbage collection before each iteration
Currently, no explicit garbage collection is performed when running
the microbenchmarks in `hg perf`. I think this is wrong because
garbage collection can have a significant impact on execution times.
And, if gc is triggered via the default heuristics, it will
fire effectively randomly during subsequent benchmark iterations
due to variable amount of garbage left over from previous runs.
Running a gc before invoking the measured function will help ensure
state is more consistent across all iterations.
author | Gregory Szorc <gregory.szorc@gmail.com> |
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date | Mon, 13 Mar 2017 18:16:42 -0700 |
parents | 751639bf6fc4 |
children | ec306bc6915b |
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# dirstateguard.py - class to allow restoring dirstate after failure # # 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. from __future__ import absolute_import from .i18n import _ from . import ( error, ) class dirstateguard(object): '''Restore dirstate at unexpected failure. At the construction, this class does: - write current ``repo.dirstate`` out, and - save ``.hg/dirstate`` into the backup file This restores ``.hg/dirstate`` from backup file, if ``release()`` is invoked before ``close()``. This just removes the backup file at ``close()`` before ``release()``. ''' def __init__(self, repo, name): self._repo = repo self._active = False self._closed = False self._suffix = '.backup.%s.%d' % (name, id(self)) repo.dirstate.savebackup(repo.currenttransaction(), self._suffix) self._active = True def __del__(self): if self._active: # still active # this may occur, even if this class is used correctly: # for example, releasing other resources like transaction # may raise exception before ``dirstateguard.release`` in # ``release(tr, ....)``. self._abort() def close(self): if not self._active: # already inactivated msg = (_("can't close already inactivated backup: dirstate%s") % self._suffix) raise error.Abort(msg) self._repo.dirstate.clearbackup(self._repo.currenttransaction(), self._suffix) self._active = False self._closed = True def _abort(self): self._repo.dirstate.restorebackup(self._repo.currenttransaction(), self._suffix) self._active = False def release(self): if not self._closed: if not self._active: # already inactivated msg = (_("can't release already inactivated backup:" " dirstate%s") % self._suffix) raise error.Abort(msg) self._abort()