branchmap: avoid ancestor computations in absence of non-continous branches
The branchhead computation is one of the more heavy operations for
bigger repositories as it has to scan all changesets and potentially
involves the expensive computation of the ancestor sets. Redo the
computation to handle the common cases directly and use tighter
conditions for when the ancestor scan is necessary. Most importantly,
avoid it completely if the non-continous branches are processed in one
update as seen in the initial computation after a clone.
For the Mercurial repository, it gives a small 2-3% performance boost.
For the NetBSD test repository, it cuts the time in half.
Differential Revision: https://phab.mercurial-scm.org/D9631
# Copyright 2017 Facebook, Inc.
#
# 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 mercurial.i18n import _
from mercurial.node import hex
from mercurial import (
bundle2,
changegroup,
error,
extensions,
pycompat,
revsetlang,
util,
)
from . import common
isremotebooksenabled = common.isremotebooksenabled
scratchbranchparttype = b'b2x:infinitepush'
def getscratchbranchparts(repo, peer, outgoing, ui, bookmark):
if not outgoing.missing:
raise error.Abort(_(b'no commits to push'))
if scratchbranchparttype not in bundle2.bundle2caps(peer):
raise error.Abort(
_(b'no server support for %r') % scratchbranchparttype
)
_validaterevset(
repo, revsetlang.formatspec(b'%ln', outgoing.missing), bookmark
)
supportedversions = changegroup.supportedoutgoingversions(repo)
# Explicitly avoid using '01' changegroup version in infinitepush to
# support general delta
supportedversions.discard(b'01')
cgversion = min(supportedversions)
_handlelfs(repo, outgoing.missing)
cg = changegroup.makestream(repo, outgoing, cgversion, b'push')
params = {}
params[b'cgversion'] = cgversion
if bookmark:
params[b'bookmark'] = bookmark
# 'prevbooknode' is necessary for pushkey reply part
params[b'bookprevnode'] = b''
bookmarks = repo._bookmarks
if bookmark in bookmarks:
params[b'bookprevnode'] = hex(bookmarks[bookmark])
# Do not send pushback bundle2 part with bookmarks if remotenames extension
# is enabled. It will be handled manually in `_push()`
if not isremotebooksenabled(ui):
params[b'pushbackbookmarks'] = b'1'
parts = []
# .upper() marks this as a mandatory part: server will abort if there's no
# handler
parts.append(
bundle2.bundlepart(
scratchbranchparttype.upper(),
advisoryparams=pycompat.iteritems(params),
data=cg,
)
)
return parts
def _validaterevset(repo, revset, bookmark):
"""Abort if the revs to be pushed aren't valid for a scratch branch."""
if not repo.revs(revset):
raise error.Abort(_(b'nothing to push'))
if bookmark:
# Allow bundle with many heads only if no bookmark is specified
heads = repo.revs(b'heads(%r)', revset)
if len(heads) > 1:
raise error.Abort(
_(b'cannot push more than one head to a scratch branch')
)
def _handlelfs(repo, missing):
"""Special case if lfs is enabled
If lfs is enabled then we need to call prepush hook
to make sure large files are uploaded to lfs
"""
try:
lfsmod = extensions.find(b'lfs')
lfsmod.wrapper.uploadblobsfromrevs(repo, missing)
except KeyError:
# Ignore if lfs extension is not enabled
return
class copiedpart(object):
"""a copy of unbundlepart content that can be consumed later"""
def __init__(self, part):
# copy "public properties"
self.type = part.type
self.id = part.id
self.mandatory = part.mandatory
self.mandatoryparams = part.mandatoryparams
self.advisoryparams = part.advisoryparams
self.params = part.params
self.mandatorykeys = part.mandatorykeys
# copy the buffer
self._io = util.stringio(part.read())
def consume(self):
return
def read(self, size=None):
if size is None:
return self._io.read()
else:
return self._io.read(size)