phases: rework the logic of _pushdiscoveryphase to bound complexity
This rework the various graph traversal in _pushdiscoveryphase to keep the
complexity in check.
This is done though a couple of things:
- first, limiting the space we have to explore, for example, if we are not in
publishing push, we don't need to consider remote draft roots that are also
draft locally, as there is nothing to be moved there.
- avoid unbounded descendant computation, and use the faster "rev between"
computation.
This provide a massive boost to performance when exchanging with repository with
a massive amount of draft, like mozilla-try:
### data-env-vars.name = mozilla-try-2023-03-22-zstd-sparse-revlog
# benchmark.name = hg.command.push
# bin-env-vars.hg.flavor = default
# bin-env-vars.hg.py-re2-module = default
# benchmark.variants.explicit-rev = all-out-heads
# benchmark.variants.issue6528 = disabled
# benchmark.variants.protocol = ssh
# benchmark.variants.reuse-external-delta-parent = default
## benchmark.variants.revs = any-1-extra-rev
before: 20.346590 seconds
after: 11.232059 seconds (-38.15%, -7.48 seconds)
## benchmark.variants.revs = any-100-extra-rev
before: 24.752051 seconds
after: 15.367412 seconds (-37.91%, -9.38 seconds)
After this changes, the push operation is still quite too slow. Some of this
can be attributed to general phases slowness (reading all the roots from disk
for example) and other know slowness (not using persistent-nodemap, branchmap,
tags, etc. We are also working on them, but with this series, phase discovery
during push no longer showing up in profile and this is a pretty nice and bit
low-hanging fruit out of the way.
### (same case as the above)
# benchmark.variants.revs = any-1-extra-rev
pre-%ln-change: 44.235070
this-changeset: 11.232059 seconds (-74.61%, -33.00 seconds)
# benchmark.variants.revs = any-100-extra-rev
pre-%ln-change: 49.234697
this-changeset: 15.367412 seconds (-68.79%, -33.87 seconds)
Note that with this change, the `hg push` performance is now much closer to the
`hg pull` performance, even it still lagging behind a bit. (and the overall
performance are still too slow).
### data-env-vars.name = mozilla-try-2023-03-22-ds2-pnm
# benchmark.variants.explicit-rev = all-out-heads
# benchmark.variants.issue6528 = disabled
# benchmark.variants.protocol = ssh
# benchmark.variants.pulled-delta-reuse-policy = default
# bin-env-vars.hg.flavor = rust
## benchmark.variants.revs = any-1-extra-rev
hg.command.pull: 6.517450
hg.command.push: 11.219888
## benchmark.variants.revs = any-100-extra-rev
hg.command.pull: 10.160991
hg.command.push: 14.251107
### data-env-vars.name = mozilla-try-2023-03-22-zstd-sparse-revlog
# bin-env-vars.hg.py-re2-module = default
# benchmark.variants.explicit-rev = all-out-heads
# benchmark.variants.issue6528 = disabled
# benchmark.variants.protocol = ssh
# benchmark.variants.pulled-delta-reuse-policy = default
## bin-env-vars.hg.flavor = default
## benchmark.variants.revs = any-1-extra-rev
hg.command.pull: 8.577772
hg.command.push: 11.232059
## bin-env-vars.hg.flavor = default
## benchmark.variants.revs = any-100-extra-rev
hg.command.pull: 13.152976
hg.command.push: 15.367412
## bin-env-vars.hg.flavor = rust
## benchmark.variants.revs = any-1-extra-rev
hg.command.pull: 8.731982
hg.command.push: 11.178751
## bin-env-vars.hg.flavor = rust
## benchmark.variants.revs = any-100-extra-rev
hg.command.pull: 13.184236
hg.command.push: 15.620843
# Copyright 2016-present Facebook. All Rights Reserved.
#
# support: fastannotate support for hgweb, and filectx
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
from mercurial import (
context as hgcontext,
dagop,
extensions,
hgweb,
patch,
util,
)
from . import (
context,
revmap,
)
class _lazyfctx:
"""delegates to fctx but do not construct fctx when unnecessary"""
def __init__(self, repo, node, path):
self._node = node
self._path = path
self._repo = repo
def node(self):
return self._node
def path(self):
return self._path
@util.propertycache
def _fctx(self):
return context.resolvefctx(self._repo, self._node, self._path)
def __getattr__(self, name):
return getattr(self._fctx, name)
def _convertoutputs(repo, annotated, contents):
"""convert fastannotate outputs to vanilla annotate format"""
# fastannotate returns: [(nodeid, linenum, path)], [linecontent]
# convert to what fctx.annotate returns: [annotateline]
results = []
fctxmap = {}
annotateline = dagop.annotateline
for i, (hsh, linenum, path) in enumerate(annotated):
if (hsh, path) not in fctxmap:
fctxmap[(hsh, path)] = _lazyfctx(repo, hsh, path)
# linenum: the user wants 1-based, we have 0-based.
lineno = linenum + 1
fctx = fctxmap[(hsh, path)]
line = contents[i]
results.append(annotateline(fctx=fctx, lineno=lineno, text=line))
return results
def _getmaster(fctx):
"""(fctx) -> str"""
return fctx._repo.ui.config(b'fastannotate', b'mainbranch') or b'default'
def _doannotate(fctx, follow=True, diffopts=None):
"""like the vanilla fctx.annotate, but do it via fastannotate, and make
the output format compatible with the vanilla fctx.annotate.
may raise Exception, and always return line numbers.
"""
master = _getmaster(fctx)
with context.fctxannotatecontext(fctx, follow, diffopts) as ac:
try:
annotated, contents = ac.annotate(
fctx.rev(), master=master, showpath=True, showlines=True
)
except Exception:
ac.rebuild() # try rebuild once
fctx._repo.ui.debug(
b'fastannotate: %s: rebuilding broken cache\n' % fctx._path
)
try:
annotated, contents = ac.annotate(
fctx.rev(), master=master, showpath=True, showlines=True
)
except Exception:
raise
assert annotated and contents
return _convertoutputs(fctx._repo, annotated, contents)
def _hgwebannotate(orig, fctx, ui):
diffopts = patch.difffeatureopts(
ui, untrusted=True, section=b'annotate', whitespace=True
)
return _doannotate(fctx, diffopts=diffopts)
def _fctxannotate(
orig, self, follow=False, linenumber=False, skiprevs=None, diffopts=None
):
if skiprevs:
# skiprevs is not supported yet
return orig(
self, follow, linenumber, skiprevs=skiprevs, diffopts=diffopts
)
try:
return _doannotate(self, follow, diffopts)
except Exception as ex:
self._repo.ui.debug(
b'fastannotate: falling back to the vanilla annotate: %r\n' % ex
)
return orig(self, follow=follow, skiprevs=skiprevs, diffopts=diffopts)
def _remotefctxannotate(orig, self, follow=False, skiprevs=None, diffopts=None):
# skipset: a set-like used to test if a fctx needs to be downloaded
with context.fctxannotatecontext(self, follow, diffopts) as ac:
skipset = revmap.revmap(ac.revmappath)
return orig(
self, follow, skiprevs=skiprevs, diffopts=diffopts, prefetchskip=skipset
)
def replacehgwebannotate():
extensions.wrapfunction(hgweb.webutil, 'annotate', _hgwebannotate)
def replacefctxannotate():
extensions.wrapfunction(hgcontext.basefilectx, 'annotate', _fctxannotate)