commit: improve the files field of changelog for merges
Currently, the files list of merge commits repeats all the deletions
(either actual deletions, or files that got renamed) that happened
between base and p2 of the merge. If p2 is the main branch, the list
can easily be much bigger than the change being merged.
This results in various problems worth improving:
- changelog is bigger than necessary
- `hg log directory` lists many unrelated merge commits, and `hg log
-v -r commit` frequently fills multiple screens worth of files
- it possibly slows down adjustlinkrev, by forcing it to read more
manifests, and that function can certainly be a bottleneck
- the server side of pulls can waste a lot of time simply opening the
filelogs for pointless files (the constant factors for opening even
a tiny filelog is apparently pretty bad)
So stop listing such files as described in the code. Impacted merge
commits and their descendants get a different hash than they would
have without this. This doesn't seem problematic, except for
convert. The previous commit helped with that in the hg->hg case (but
if you do svn->hg twice from scratch, hashes can still change).
The rest of the description is numbers. I don't have much to report,
because recreating the files list of existing repositories is not
easy:
- debugupgradeformat and bundle/unbundle don't recreate the list
- export/import tends to choke quickly applying patches or on
description that contain diffs,
- merge commits from the convert extension don't have the right files
list for reasons orthogonal to the current commit
- replaying the merge with hg update/hg merge/hg revert --all/hg
commit can end up failing in hg revert
- I wasn't sure that using debugsetparents + debugrebuilddirstate
would really build the right thing
I measured commit time before and after this change, in a case with no
files filtered out, several files filtered out (no difference) and 5k
files filtered out (+1% time).
Recreating the 100 more recent merges in a private repo, the
concatenated uncompressed files lists goes from 1.12MB to
0.52MB. Excluding 3 merges that are not representative, then the size
goes from 570k to 15k.
I converted part of mozilla-central, and observed file list shrinking
quite a bit too, starting at the very first merge, 733641d9feaf, going
from 550 files to 10 files (although they have relatively few merges,
so they probably wouldn't care).
Differential Revision: https://phab.mercurial-scm.org/D6613
# gnuarch.py - GNU Arch support for the convert extension
#
# Copyright 2008, 2009 Aleix Conchillo Flaque <aleix@member.fsf.org>
# and others
#
# 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
import email.parser as emailparser
import os
import shutil
import stat
import tempfile
from mercurial.i18n import _
from mercurial import (
encoding,
error,
pycompat,
util,
)
from mercurial.utils import (
dateutil,
procutil,
)
from . import common
class gnuarch_source(common.converter_source, common.commandline):
class gnuarch_rev(object):
def __init__(self, rev):
self.rev = rev
self.summary = ''
self.date = None
self.author = ''
self.continuationof = None
self.add_files = []
self.mod_files = []
self.del_files = []
self.ren_files = {}
self.ren_dirs = {}
def __init__(self, ui, repotype, path, revs=None):
super(gnuarch_source, self).__init__(ui, repotype, path, revs=revs)
if not os.path.exists(os.path.join(path, '{arch}')):
raise common.NoRepo(_("%s does not look like a GNU Arch repository")
% path)
# Could use checktool, but we want to check for baz or tla.
self.execmd = None
if procutil.findexe('baz'):
self.execmd = 'baz'
else:
if procutil.findexe('tla'):
self.execmd = 'tla'
else:
raise error.Abort(_('cannot find a GNU Arch tool'))
common.commandline.__init__(self, ui, self.execmd)
self.path = os.path.realpath(path)
self.tmppath = None
self.treeversion = None
self.lastrev = None
self.changes = {}
self.parents = {}
self.tags = {}
self.catlogparser = emailparser.Parser()
self.encoding = encoding.encoding
self.archives = []
def before(self):
# Get registered archives
self.archives = [i.rstrip('\n')
for i in self.runlines0('archives', '-n')]
if self.execmd == 'tla':
output = self.run0('tree-version', self.path)
else:
output = self.run0('tree-version', '-d', self.path)
self.treeversion = output.strip()
# Get name of temporary directory
version = self.treeversion.split('/')
self.tmppath = os.path.join(tempfile.gettempdir(),
'hg-%s' % version[1])
# Generate parents dictionary
self.parents[None] = []
treeversion = self.treeversion
child = None
while treeversion:
self.ui.status(_('analyzing tree version %s...\n') % treeversion)
archive = treeversion.split('/')[0]
if archive not in self.archives:
self.ui.status(_('tree analysis stopped because it points to '
'an unregistered archive %s...\n') % archive)
break
# Get the complete list of revisions for that tree version
output, status = self.runlines('revisions', '-r', '-f', treeversion)
self.checkexit(status, 'failed retrieving revisions for %s'
% treeversion)
# No new iteration unless a revision has a continuation-of header
treeversion = None
for l in output:
rev = l.strip()
self.changes[rev] = self.gnuarch_rev(rev)
self.parents[rev] = []
# Read author, date and summary
catlog, status = self.run('cat-log', '-d', self.path, rev)
if status:
catlog = self.run0('cat-archive-log', rev)
self._parsecatlog(catlog, rev)
# Populate the parents map
self.parents[child].append(rev)
# Keep track of the current revision as the child of the next
# revision scanned
child = rev
# Check if we have to follow the usual incremental history
# or if we have to 'jump' to a different treeversion given
# by the continuation-of header.
if self.changes[rev].continuationof:
treeversion = '--'.join(
self.changes[rev].continuationof.split('--')[:-1])
break
# If we reached a base-0 revision w/o any continuation-of
# header, it means the tree history ends here.
if rev[-6:] == 'base-0':
break
def after(self):
self.ui.debug('cleaning up %s\n' % self.tmppath)
shutil.rmtree(self.tmppath, ignore_errors=True)
def getheads(self):
return self.parents[None]
def getfile(self, name, rev):
if rev != self.lastrev:
raise error.Abort(_('internal calling inconsistency'))
if not os.path.lexists(os.path.join(self.tmppath, name)):
return None, None
return self._getfile(name, rev)
def getchanges(self, rev, full):
if full:
raise error.Abort(_("convert from arch does not support --full"))
self._update(rev)
changes = []
copies = {}
for f in self.changes[rev].add_files:
changes.append((f, rev))
for f in self.changes[rev].mod_files:
changes.append((f, rev))
for f in self.changes[rev].del_files:
changes.append((f, rev))
for src in self.changes[rev].ren_files:
to = self.changes[rev].ren_files[src]
changes.append((src, rev))
changes.append((to, rev))
copies[to] = src
for src in self.changes[rev].ren_dirs:
to = self.changes[rev].ren_dirs[src]
chgs, cps = self._rendirchanges(src, to)
changes += [(f, rev) for f in chgs]
copies.update(cps)
self.lastrev = rev
return sorted(set(changes)), copies, set()
def getcommit(self, rev):
changes = self.changes[rev]
return common.commit(author=changes.author, date=changes.date,
desc=changes.summary, parents=self.parents[rev],
rev=rev)
def gettags(self):
return self.tags
def _execute(self, cmd, *args, **kwargs):
cmdline = [self.execmd, cmd]
cmdline += args
cmdline = [procutil.shellquote(arg) for arg in cmdline]
cmdline += ['>', os.devnull, '2>', os.devnull]
cmdline = procutil.quotecommand(' '.join(cmdline))
self.ui.debug(cmdline, '\n')
return os.system(pycompat.rapply(procutil.tonativestr, cmdline))
def _update(self, rev):
self.ui.debug('applying revision %s...\n' % rev)
changeset, status = self.runlines('replay', '-d', self.tmppath,
rev)
if status:
# Something went wrong while merging (baz or tla
# issue?), get latest revision and try from there
shutil.rmtree(self.tmppath, ignore_errors=True)
self._obtainrevision(rev)
else:
old_rev = self.parents[rev][0]
self.ui.debug('computing changeset between %s and %s...\n'
% (old_rev, rev))
self._parsechangeset(changeset, rev)
def _getfile(self, name, rev):
mode = os.lstat(os.path.join(self.tmppath, name)).st_mode
if stat.S_ISLNK(mode):
data = util.readlink(os.path.join(self.tmppath, name))
if mode:
mode = 'l'
else:
mode = ''
else:
data = util.readfile(os.path.join(self.tmppath, name))
mode = (mode & 0o111) and 'x' or ''
return data, mode
def _exclude(self, name):
exclude = ['{arch}', '.arch-ids', '.arch-inventory']
for exc in exclude:
if name.find(exc) != -1:
return True
return False
def _readcontents(self, path):
files = []
contents = os.listdir(path)
while len(contents) > 0:
c = contents.pop()
p = os.path.join(path, c)
# os.walk could be used, but here we avoid internal GNU
# Arch files and directories, thus saving a lot time.
if not self._exclude(p):
if os.path.isdir(p):
contents += [os.path.join(c, f) for f in os.listdir(p)]
else:
files.append(c)
return files
def _rendirchanges(self, src, dest):
changes = []
copies = {}
files = self._readcontents(os.path.join(self.tmppath, dest))
for f in files:
s = os.path.join(src, f)
d = os.path.join(dest, f)
changes.append(s)
changes.append(d)
copies[d] = s
return changes, copies
def _obtainrevision(self, rev):
self.ui.debug('obtaining revision %s...\n' % rev)
output = self._execute('get', rev, self.tmppath)
self.checkexit(output)
self.ui.debug('analyzing revision %s...\n' % rev)
files = self._readcontents(self.tmppath)
self.changes[rev].add_files += files
def _stripbasepath(self, path):
if path.startswith('./'):
return path[2:]
return path
def _parsecatlog(self, data, rev):
try:
catlog = self.catlogparser.parsestr(data)
# Commit date
self.changes[rev].date = dateutil.datestr(
dateutil.strdate(catlog['Standard-date'],
'%Y-%m-%d %H:%M:%S'))
# Commit author
self.changes[rev].author = self.recode(catlog['Creator'])
# Commit description
self.changes[rev].summary = '\n\n'.join((catlog['Summary'],
catlog.get_payload()))
self.changes[rev].summary = self.recode(self.changes[rev].summary)
# Commit revision origin when dealing with a branch or tag
if 'Continuation-of' in catlog:
self.changes[rev].continuationof = self.recode(
catlog['Continuation-of'])
except Exception:
raise error.Abort(_('could not parse cat-log of %s') % rev)
def _parsechangeset(self, data, rev):
for l in data:
l = l.strip()
# Added file (ignore added directory)
if l.startswith('A') and not l.startswith('A/'):
file = self._stripbasepath(l[1:].strip())
if not self._exclude(file):
self.changes[rev].add_files.append(file)
# Deleted file (ignore deleted directory)
elif l.startswith('D') and not l.startswith('D/'):
file = self._stripbasepath(l[1:].strip())
if not self._exclude(file):
self.changes[rev].del_files.append(file)
# Modified binary file
elif l.startswith('Mb'):
file = self._stripbasepath(l[2:].strip())
if not self._exclude(file):
self.changes[rev].mod_files.append(file)
# Modified link
elif l.startswith('M->'):
file = self._stripbasepath(l[3:].strip())
if not self._exclude(file):
self.changes[rev].mod_files.append(file)
# Modified file
elif l.startswith('M'):
file = self._stripbasepath(l[1:].strip())
if not self._exclude(file):
self.changes[rev].mod_files.append(file)
# Renamed file (or link)
elif l.startswith('=>'):
files = l[2:].strip().split(' ')
if len(files) == 1:
files = l[2:].strip().split('\t')
src = self._stripbasepath(files[0])
dst = self._stripbasepath(files[1])
if not self._exclude(src) and not self._exclude(dst):
self.changes[rev].ren_files[src] = dst
# Conversion from file to link or from link to file (modified)
elif l.startswith('ch'):
file = self._stripbasepath(l[2:].strip())
if not self._exclude(file):
self.changes[rev].mod_files.append(file)
# Renamed directory
elif l.startswith('/>'):
dirs = l[2:].strip().split(' ')
if len(dirs) == 1:
dirs = l[2:].strip().split('\t')
src = self._stripbasepath(dirs[0])
dst = self._stripbasepath(dirs[1])
if not self._exclude(src) and not self._exclude(dst):
self.changes[rev].ren_dirs[src] = dst