localrepo: cache types for filtered repos (issue5043)
Python introduces a reference cycle on dynamically created types
via __mro__, making them very easy to leak. See
https://bugs.python.org/issue17950.
Previously, repo.filtered() created a type on every invocation.
Long-running processes (like `hg convert`) could call this
function thousands of times, leading to a steady memory leak.
Since we're Unable to stop the leak because this is a bug in
Python, the next best thing is to contain it.
This patch adds a cache of of the dynamically generated repoview/filter
types on the localrepo object. Since we only generate each type
once, we cap the amount of memory that can leak to something
reasonable.
After this change, `hg convert` no longer leaks memory on every
revision. The process will likely grow memory usage over time due
to e.g. larger manifests. But there are no leaks.
# mergeutil.py - help for merge processing in 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.
from __future__ import absolute_import
from .i18n import _
from . import (
error,
)
def checkunresolved(ms):
if list(ms.unresolved()):
raise error.Abort(_("unresolved merge conflicts "
"(see 'hg help resolve')"))
if ms.mdstate() != 's' or list(ms.driverresolved()):
raise error.Abort(_('driver-resolved merge conflicts'),
hint=_('run "hg resolve --all" to resolve'))