"""Extension to try and speed up transfer of obsolete markers.
Mercurial 2.6 transfers obsolete markers in the dumbest way possible:
it simply transfers all of them to the server on every
operation. While this /works/, it's not ideal because it's a large
amount of extra data for users to pull down (1.9M for the 17k obsolete
markers in hg-crew as of this writing in late July 2013). It's also
frustrating because this transfer takes a nontrivial amount of time.
You can specify a strategy with the config knob
obsolete.syncstrategy. Current strategies are "stock" and
"boxfill". Default strategy is presently boxfill.
TODO(durin42): consider better names for sync strategies.
"""
import sys
from mercurial import commands
from mercurial import extensions
from mercurial import obsolete
from mercurial import node
from mercurial.i18n import _
_strategies = {
'stock': obsolete.syncpush,
}
def _strategy(name, default=False):
def inner(func):
_strategies[name] = func
if default:
_strategies[None] = func
return func
return inner
def syncpushwrapper(orig, repo, remote):
stratfn = _strategies[repo.ui.config('obsolete', 'syncstrategy')]
return stratfn(repo, remote)
extensions.wrapfunction(obsolete, 'syncpush', syncpushwrapper)
def pushmarkerwrapper(orig, repo, *args):
if repo.ui.config('obsolete', 'syncstrategy') == 'stock':
return orig(repo, *args)
# We shouldn't need to do this, since we transmit markers
# effectively during push in localrepo. Just return success.
return 1
def _getoutgoing():
f = sys._getframe(4)
return f.f_locals['outgoing']
@_strategy('boxfill', default=True)
def boxfill(repo, remote):
"""The "fill in the box" strategy from the 2.6 sprint.
See the notes[0] from the 2.6 sprint for what "fill in the box"
means here. It's a fairly subtle algorithm, which may have
surprising behavior at times, but was the least-bad option
proposed at the sprint.
[0]: https://bitbucket.org/durin42/2.6sprint-notes/src/tip/mercurial26-obsstore-rev.1398.txt
"""
outgoing = _getoutgoing()
urepo = repo.unfiltered()
# need to collect obsolete markers which list any of
# outgoing.missing as a successor (transitively), as well as any
# kill markers for dead nodes descended from any of the precursors
# of outgoing.missing.
boxedges = urepo.revs(
'(descendants(precursors(%ln)) or descendants(%ln)) and hidden()',
outgoing.missing, outgoing.missing)
transmit = []
for node in boxedges:
transmit.extend(obsolete.successormarkers(urepo[node]))
xmit, total = len(transmit), len(repo.obsstore._all)
repo.ui.status(
'boxpush: about to transmit %d obsolete markers (%d markers total)\n'
% (xmit, total))
parts, size, chunk = [], 0, 0
for marker in transmit:
enc = obsolete._encodeonemarker(_markertuple(marker))
parts.append(enc)
size += len(enc)
if size > obsolete._maxpayload:
repo.ui.note(
'boxpush: sending a chunk of obsolete markers\n')
data = ''.join([obsolete._pack('>B', _fmversion)], parts)
remote.pushkey('obsolete', 'dump%d' % chunk, base85.b85encode(data))
parts, size = [], 0
chunk += 1
def _markertuple(marker):
return marker._data