##// END OF EJS Templates
changegroup: increase write buffer size to 128k...
changegroup: increase write buffer size to 128k By default, Python defers to the operating system for choosing the default buffer size on opened files. On my Linux machine, the default is 4k, which is really small for 2016. This patch bumps the write buffer size when writing changegroups/bundles to 128k. This matches the 128k read buffer we already use on revlogs. It's worth noting that this only impacts when writing to an explicit file (such as during `hg bundle`). Buffers when writing to bundle files via the repo vfs or to a temporary file are not impacted. When producing a none-v2 bundle file of the mozilla-unified repository, this change caused the number of write() system calls to drop from 952,449 to 29,788. After this change, the most frequent system calls are fstat(), read(), lseek(), and open(). There were 2,523,672 system calls after this patch (so a net decrease of ~950k is statistically significant). This change shows no performance change on my system. But I have a high-end system with a fast SSD. It is quite possible this change will have a significant impact on network file systems, where extra network round trips due to excessive I/O system calls could introduce significant latency.

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unionrepo.py
262 lines | 9.0 KiB | text/x-python | PythonLexer
# unionrepo.py - repository class for viewing union of repository changesets
#
# Derived from bundlerepo.py
# Copyright 2006, 2007 Benoit Boissinot <bboissin@gmail.com>
# Copyright 2013 Unity Technologies, Mads Kiilerich <madski@unity3d.com>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
"""Repository class for "in-memory pull" of one local repository to another,
allowing operations like diff and log with revsets.
"""
from __future__ import absolute_import
import os
from .i18n import _
from .node import nullid
from . import (
changelog,
cmdutil,
error,
filelog,
localrepo,
manifest,
mdiff,
pathutil,
revlog,
scmutil,
util,
)
class unionrevlog(revlog.revlog):
def __init__(self, opener, indexfile, revlog2, linkmapper):
# How it works:
# To retrieve a revision, we just need to know the node id so we can
# look it up in revlog2.
#
# To differentiate a rev in the second revlog from a rev in the revlog,
# we check revision against repotiprev.
opener = scmutil.readonlyvfs(opener)
revlog.revlog.__init__(self, opener, indexfile)
self.revlog2 = revlog2
n = len(self)
self.repotiprev = n - 1
self.bundlerevs = set() # used by 'bundle()' revset expression
for rev2 in self.revlog2:
rev = self.revlog2.index[rev2]
# rev numbers - in revlog2, very different from self.rev
_start, _csize, _rsize, base, linkrev, p1rev, p2rev, node = rev
flags = _start & 0xFFFF
if linkmapper is None: # link is to same revlog
assert linkrev == rev2 # we never link back
link = n
else: # rev must be mapped from repo2 cl to unified cl by linkmapper
link = linkmapper(linkrev)
if linkmapper is not None: # link is to same revlog
base = linkmapper(base)
if node in self.nodemap:
# this happens for the common revlog revisions
self.bundlerevs.add(self.nodemap[node])
continue
p1node = self.revlog2.node(p1rev)
p2node = self.revlog2.node(p2rev)
e = (flags, None, None, base,
link, self.rev(p1node), self.rev(p2node), node)
self.index.insert(-1, e)
self.nodemap[node] = n
self.bundlerevs.add(n)
n += 1
def _chunk(self, rev):
if rev <= self.repotiprev:
return revlog.revlog._chunk(self, rev)
return self.revlog2._chunk(self.node(rev))
def revdiff(self, rev1, rev2):
"""return or calculate a delta between two revisions"""
if rev1 > self.repotiprev and rev2 > self.repotiprev:
return self.revlog2.revdiff(
self.revlog2.rev(self.node(rev1)),
self.revlog2.rev(self.node(rev2)))
elif rev1 <= self.repotiprev and rev2 <= self.repotiprev:
return self.baserevdiff(rev1, rev2)
return mdiff.textdiff(self.revision(self.node(rev1)),
self.revision(self.node(rev2)))
def revision(self, nodeorrev):
"""return an uncompressed revision of a given node or revision
number.
"""
if isinstance(nodeorrev, int):
rev = nodeorrev
node = self.node(rev)
else:
node = nodeorrev
rev = self.rev(node)
if node == nullid:
return ""
if rev > self.repotiprev:
text = self.revlog2.revision(node)
self._cache = (node, rev, text)
else:
text = self.baserevision(rev)
# already cached
return text
def baserevision(self, nodeorrev):
# Revlog subclasses may override 'revision' method to modify format of
# content retrieved from revlog. To use unionrevlog with such class one
# needs to override 'baserevision' and make more specific call here.
return revlog.revlog.revision(self, nodeorrev)
def baserevdiff(self, rev1, rev2):
# Exists for the same purpose as baserevision.
return revlog.revlog.revdiff(self, rev1, rev2)
def addrevision(self, text, transaction, link, p1=None, p2=None, d=None):
raise NotImplementedError
def addgroup(self, revs, linkmapper, transaction):
raise NotImplementedError
def strip(self, rev, minlink):
raise NotImplementedError
def checksize(self):
raise NotImplementedError
class unionchangelog(unionrevlog, changelog.changelog):
def __init__(self, opener, opener2):
changelog.changelog.__init__(self, opener)
linkmapper = None
changelog2 = changelog.changelog(opener2)
unionrevlog.__init__(self, opener, self.indexfile, changelog2,
linkmapper)
def baserevision(self, nodeorrev):
# Although changelog doesn't override 'revision' method, some extensions
# may replace this class with another that does. Same story with
# manifest and filelog classes.
return changelog.changelog.revision(self, nodeorrev)
def baserevdiff(self, rev1, rev2):
return changelog.changelog.revdiff(self, rev1, rev2)
class unionmanifest(unionrevlog, manifest.manifest):
def __init__(self, opener, opener2, linkmapper):
manifest.manifest.__init__(self, opener)
manifest2 = manifest.manifest(opener2)
unionrevlog.__init__(self, opener, self.indexfile, manifest2,
linkmapper)
def baserevision(self, nodeorrev):
return manifest.manifest.revision(self, nodeorrev)
def baserevdiff(self, rev1, rev2):
return manifest.manifest.revdiff(self, rev1, rev2)
class unionfilelog(unionrevlog, filelog.filelog):
def __init__(self, opener, path, opener2, linkmapper, repo):
filelog.filelog.__init__(self, opener, path)
filelog2 = filelog.filelog(opener2, path)
unionrevlog.__init__(self, opener, self.indexfile, filelog2,
linkmapper)
self._repo = repo
def baserevision(self, nodeorrev):
return filelog.filelog.revision(self, nodeorrev)
def baserevdiff(self, rev1, rev2):
return filelog.filelog.revdiff(self, rev1, rev2)
def iscensored(self, rev):
"""Check if a revision is censored."""
if rev <= self.repotiprev:
return filelog.filelog.iscensored(self, rev)
node = self.node(rev)
return self.revlog2.iscensored(self.revlog2.rev(node))
class unionpeer(localrepo.localpeer):
def canpush(self):
return False
class unionrepository(localrepo.localrepository):
def __init__(self, ui, path, path2):
localrepo.localrepository.__init__(self, ui, path)
self.ui.setconfig('phases', 'publish', False, 'unionrepo')
self._url = 'union:%s+%s' % (util.expandpath(path),
util.expandpath(path2))
self.repo2 = localrepo.localrepository(ui, path2)
@localrepo.unfilteredpropertycache
def changelog(self):
return unionchangelog(self.svfs, self.repo2.svfs)
def _clrev(self, rev2):
"""map from repo2 changelog rev to temporary rev in self.changelog"""
node = self.repo2.changelog.node(rev2)
return self.changelog.rev(node)
@localrepo.unfilteredpropertycache
def manifest(self):
return unionmanifest(self.svfs, self.repo2.svfs,
self.unfiltered()._clrev)
def url(self):
return self._url
def file(self, f):
return unionfilelog(self.svfs, f, self.repo2.svfs,
self.unfiltered()._clrev, self)
def close(self):
self.repo2.close()
def cancopy(self):
return False
def peer(self):
return unionpeer(self)
def getcwd(self):
return os.getcwd() # always outside the repo
def instance(ui, path, create):
if create:
raise error.Abort(_('cannot create new union repository'))
parentpath = ui.config("bundle", "mainreporoot", "")
if not parentpath:
# try to find the correct path to the working directory repo
parentpath = cmdutil.findrepo(os.getcwd())
if parentpath is None:
parentpath = ''
if parentpath:
# Try to make the full path relative so we get a nice, short URL.
# In particular, we don't want temp dir names in test outputs.
cwd = os.getcwd()
if parentpath == cwd:
parentpath = ''
else:
cwd = pathutil.normasprefix(cwd)
if parentpath.startswith(cwd):
parentpath = parentpath[len(cwd):]
if path.startswith('union:'):
s = path.split(":", 1)[1].split("+", 1)
if len(s) == 1:
repopath, repopath2 = parentpath, s[0]
else:
repopath, repopath2 = s
else:
repopath, repopath2 = parentpath, path
return unionrepository(ui, repopath, repopath2)