revlog: add a small cache of unfiltered chunk
This can provides a massive boost to the reading of multiple revision and the
computation of a valid delta chain.
This greatly help operation like `hg log --patch`, delta computation (helping
pull/unbundle), linkrev adjustment (helping copy tracing).
A first round of benchmark for `hg log --patch --limit 1000` shows improvement
in the 10-20% range on "small" repository like pypy or mercurial and large
improvements (about 33%) for more complex ones like netbeans and mozilla's.
These speeds up are consistent with the improvement to `hg pull` (from a server
sending poor deltas) I saw benchmarking this last year. Further benchmark will
be run during the freeze.
I added some configuration in the experimental space to be able to further test
the effect of various tuning for now. This feature should fit well in the
"usage/resource profile" configuration that we should land next cycle.
When it does not provides a benefit the overhead of the cache seem to be around
2%, a small price for the big improvement. In addition I believe we could shave
most of this overhead with a more efficent lru implementation.
# fetch.py - pull and merge remote changes
#
# Copyright 2006 Vadim Gelfer <vadim.gelfer@gmail.com>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
'''pull, update and merge in one command (DEPRECATED)'''
from mercurial.i18n import _
from mercurial.node import short
from mercurial import (
cmdutil,
error,
exchange,
hg,
lock,
pycompat,
registrar,
)
from mercurial.utils import (
dateutil,
urlutil,
)
release = lock.release
cmdtable = {}
command = registrar.command(cmdtable)
# Note for extension authors: ONLY specify testedwith = 'ships-with-hg-core' for
# extensions which SHIP WITH MERCURIAL. Non-mainline extensions should
# be specifying the version(s) of Mercurial they are tested with, or
# leave the attribute unspecified.
testedwith = b'ships-with-hg-core'
@command(
b'fetch',
[
(
b'r',
b'rev',
[],
_(b'a specific revision you would like to pull'),
_(b'REV'),
),
(b'', b'edit', None, _(b'invoke editor on commit messages')),
(b'', b'force-editor', None, _(b'edit commit message (DEPRECATED)')),
(b'', b'switch-parent', None, _(b'switch parents when merging')),
]
+ cmdutil.commitopts
+ cmdutil.commitopts2
+ cmdutil.remoteopts,
_(b'hg fetch [SOURCE]'),
helpcategory=command.CATEGORY_REMOTE_REPO_MANAGEMENT,
)
def fetch(ui, repo, source=b'default', **opts):
"""pull changes from a remote repository, merge new changes if needed.
This finds all changes from the repository at the specified path
or URL and adds them to the local repository.
If the pulled changes add a new branch head, the head is
automatically merged, and the result of the merge is committed.
Otherwise, the working directory is updated to include the new
changes.
When a merge is needed, the working directory is first updated to
the newly pulled changes. Local changes are then merged into the
pulled changes. To switch the merge order, use --switch-parent.
See :hg:`help dates` for a list of formats valid for -d/--date.
Returns 0 on success.
"""
date = opts.get('date')
if date:
opts['date'] = dateutil.parsedate(date)
parent = repo.dirstate.p1()
branch = repo.dirstate.branch()
try:
branchnode = repo.branchtip(branch)
except error.RepoLookupError:
branchnode = None
if parent != branchnode:
raise error.Abort(
_(b'working directory not at branch tip'),
hint=_(b"use 'hg update' to check out branch tip"),
)
wlock = lock = None
try:
wlock = repo.wlock()
lock = repo.lock()
cmdutil.bailifchanged(repo)
bheads = repo.branchheads(branch)
bheads = [head for head in bheads if len(repo[head].children()) == 0]
if len(bheads) > 1:
raise error.Abort(
_(
b'multiple heads in this branch '
b'(use "hg heads ." and "hg merge" to merge)'
)
)
path = urlutil.get_unique_pull_path_obj(b'fetch', ui, source)
other = hg.peer(repo, pycompat.byteskwargs(opts), path)
ui.status(_(b'pulling from %s\n') % urlutil.hidepassword(path.loc))
revs = None
if opts['rev']:
try:
revs = [other.lookup(rev) for rev in opts['rev']]
except error.CapabilityError:
err = _(
b"other repository doesn't support revision lookup, "
b"so a rev cannot be specified."
)
raise error.Abort(err)
# Are there any changes at all?
modheads = exchange.pull(repo, other, heads=revs).cgresult
if modheads == 0:
return 0
# Is this a simple fast-forward along the current branch?
newheads = repo.branchheads(branch)
newchildren = repo.changelog.nodesbetween([parent], newheads)[2]
if len(newheads) == 1 and len(newchildren):
if newchildren[0] != parent:
return hg.update(repo, newchildren[0])
else:
return 0
# Are there more than one additional branch heads?
newchildren = [n for n in newchildren if n != parent]
newparent = parent
if newchildren:
newparent = newchildren[0]
hg.clean(repo, newparent)
newheads = [n for n in newheads if n != newparent]
if len(newheads) > 1:
ui.status(
_(
b'not merging with %d other new branch heads '
b'(use "hg heads ." and "hg merge" to merge them)\n'
)
% (len(newheads) - 1)
)
return 1
if not newheads:
return 0
# Otherwise, let's merge.
err = False
if newheads:
# By default, we consider the repository we're pulling
# *from* as authoritative, so we merge our changes into
# theirs.
if opts['switch_parent']:
firstparent, secondparent = newparent, newheads[0]
else:
firstparent, secondparent = newheads[0], newparent
ui.status(
_(b'updating to %d:%s\n')
% (repo.changelog.rev(firstparent), short(firstparent))
)
hg.clean(repo, firstparent)
p2ctx = repo[secondparent]
ui.status(
_(b'merging with %d:%s\n') % (p2ctx.rev(), short(secondparent))
)
err = hg.merge(p2ctx, remind=False)
if not err:
# we don't translate commit messages
message = cmdutil.logmessage(ui, pycompat.byteskwargs(opts)) or (
b'Automated merge with %s' % urlutil.removeauth(other.url())
)
editopt = opts.get('edit') or opts.get('force_editor')
editor = cmdutil.getcommiteditor(edit=editopt, editform=b'fetch')
n = repo.commit(message, opts['user'], opts['date'], editor=editor)
ui.status(
_(b'new changeset %d:%s merges remote changes with local\n')
% (repo.changelog.rev(n), short(n))
)
return err
finally:
release(lock, wlock)