perf: clear vfs audit_cache before each run
When generating a stream clone, we spend a large amount of time auditing path.
Before this changes, the first run was warming the vfs cache for the other
runs, leading to a large runtime difference and a "faulty" reported timing for
the operation.
We now clear this important cache between run to get a more realistic timing.
Below are some example of median time change when clearing these cases. The
maximum time for a run did not changed significantly.
### data-env-vars.name = mozilla-central-2018-08-01-zstd-sparse-revlog
# benchmark.name = hg.perf.exchange.stream.generate
# bin-env-vars.hg.flavor = default
# bin-env-vars.hg.py-re2-module = default
# benchmark.variants.version = latest
no-clearing: 17.289905
cache-clearing: 21.587965 (+24.86%, +4.30)
## data-env-vars.name = mozilla-central-2024-03-22-zstd-sparse-revlog
no-clearing: 32.670748
cache-clearing: 40.467095 (+23.86%, +7.80)
## data-env-vars.name = mozilla-try-2019-02-18-zstd-sparse-revlog
no-clearing: 37.838858
cache-clearing: 46.072749 (+21.76%, +8.23)
## data-env-vars.name = mozilla-unified-2024-03-22-zstd-sparse-revlog
no-clearing: 32.969395
cache-clearing: 39.646209 (+20.25%, +6.68)
In addition, this significantly reduce the timing difference between the
performance command, from the perf extensions and a `real `hg bundle` call
producing a stream bundle. Some significant differences remain especially on
the "mozilla-try" repositories, but they are now smaller.
Note that some of that difference will actually not be
attributable to the stream generation (like maybe phases or branch map
computation).
Below are some benchmarks done on a currently draft changeset fixing some
unrelated slowness in `hg bundle` (34a78972af409d1ff37c29e60f6ca811ad1a457d)
### data-env-vars.name = mozilla-central-2018-08-01-zstd-sparse-revlog
# bin-env-vars.hg.flavor = default
# bin-env-vars.hg.py-re2-module = default
hg.perf.exchange.stream.generate: 21.587965
hg.command.bundle: 24.301799 (+12.57%, +2.71)
## data-env-vars.name = mozilla-central-2024-03-22-zstd-sparse-revlog
hg.perf.exchange.stream.generate: 40.467095
hg.command.bundle: 44.831317 (+10.78%, +4.36)
## data-env-vars.name = mozilla-unified-2024-03-22-zstd-sparse-revlog
hg.perf.exchange.stream.generate: 39.646209
hg.command.bundle: 45.395258 (+14.50%, +5.75)
## data-env-vars.name = mozilla-try-2019-02-18-zstd-sparse-revlog
hg.perf.exchange.stream.generate: 46.072749
hg.command.bundle: 55.882608 (+21.29%, +9.81)
## data-env-vars.name = mozilla-try-2023-03-22-zlib-general-delta
hg.perf.exchange.stream.generate: 334.716708
hg.command.bundle: 377.856767 (+12.89%, +43.14)
## data-env-vars.name = mozilla-try-2023-03-22-zstd-sparse-revlog
hg.perf.exchange.stream.generate: 302.972301
hg.command.bundle: 326.098755 (+7.63%, +23.13)
$ . "$TESTDIR/narrow-library.sh"
$ hg init master
$ cd master
$ mkdir inside
$ echo inside > inside/f1
$ mkdir outside
$ echo outside > outside/f2
$ mkdir patchdir
$ echo patch_this > patchdir/f3
$ hg ci -Aqm 'initial'
$ cd ..
$ hg clone --narrow ssh://user@dummy/master narrow --include inside
requesting all changes
adding changesets
adding manifests
adding file changes
added 1 changesets with 1 changes to 1 files
new changesets dff6a2a6d433
updating to branch default
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ cd narrow
$ mkdir outside
$ echo other_contents > outside/f2
$ hg tracked | grep outside
[1]
$ hg files | grep outside
[1]
$ hg status
`hg status` did not add outside.
$ hg tracked | grep outside
[1]
$ hg files | grep outside
[1]
Unfortunately this is not really a candidate for adding to narrowhg proper,
since it depends on some other source for providing the manifests (when using
treemanifests) and file contents. Something like a virtual filesystem and/or
remotefilelog. We want to be useful when not using those systems, so we do not
have this method available in narrowhg proper at the moment.
$ cat > "$TESTTMP/expand_extension.py" <<EOF
> import os
> import sys
>
> from mercurial import encoding
> from mercurial import extensions
> from mercurial import localrepo
> from mercurial import match as matchmod
> from mercurial import narrowspec
> from mercurial import patch
> from mercurial import util as hgutil
>
> narrowspecexpanded = False
> def expandnarrowspec(ui, repo, newincludes=None):
> if not newincludes:
> return
> if getattr(repo, '_narrowspecexpanded', False):
> return
> repo._narrowspecexpanded = True
> import sys
> newincludes = set([newincludes])
> includes, excludes = repo.narrowpats
> currentmatcher = narrowspec.match(repo.root, includes, excludes)
> includes = includes | newincludes
> if not repo.currenttransaction():
> ui.develwarn(b'expandnarrowspec called outside of transaction!')
> repo.setnarrowpats(includes, excludes)
> narrowspec.copytoworkingcopy(repo)
> newmatcher = narrowspec.match(repo.root, includes, excludes)
> added = matchmod.differencematcher(newmatcher, currentmatcher)
> with repo.dirstate.changing_parents(repo):
> for f in repo[b'.'].manifest().walk(added):
> repo.dirstate.update_file(
> f,
> p1_tracked=True,
> wc_tracked=True,
> possibly_dirty=True,
> )
>
> def reposetup(ui, repo):
> class expandingrepo(repo.__class__):
> def narrowmatch(self, *args, **kwargs):
> with repo.wlock(), repo.lock(), repo.transaction(
> b'expandnarrowspec'):
> expandnarrowspec(ui, repo,
> encoding.environ.get(b'DIRSTATEINCLUDES'))
> return super(expandingrepo, self).narrowmatch(*args, **kwargs)
> repo.__class__ = expandingrepo
>
> def extsetup(unused_ui):
> def overridepatch(orig, ui, repo, *args, **kwargs):
> with repo.wlock():
> expandnarrowspec(ui, repo, encoding.environ.get(b'PATCHINCLUDES'))
> return orig(ui, repo, *args, **kwargs)
>
> extensions.wrapfunction(patch, 'patch', overridepatch)
> EOF
$ cat >> ".hg/hgrc" <<EOF
> [extensions]
> expand_extension = $TESTTMP/expand_extension.py
> EOF
Since we do not have the ability to rely on a virtual filesystem or
remotefilelog in the test, we just fake it by copying the data from the 'master'
repo.
$ cp -a ../master/.hg/store/data/* .hg/store/data
Do that for patchdir as well.
$ cp -a ../master/patchdir .
`hg status` will now add outside, but not patchdir.
$ DIRSTATEINCLUDES=path:outside hg status
M outside/f2
$ hg tracked | grep outside
I path:outside
$ hg files | grep outside > /dev/null
$ hg tracked | grep patchdir
[1]
$ hg files | grep patchdir
[1]
Get rid of the modification to outside/f2.
$ hg update -C .
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
This patch will not apply cleanly at the moment, so `hg import` will break
$ cat > "$TESTTMP/foo.patch" <<EOF
> --- patchdir/f3
> +++ patchdir/f3
> @@ -1,1 +1,1 @@
> -this should be "patch_this", but its not, so patch fails
> +this text is irrelevant
> EOF
$ PATCHINCLUDES=path:patchdir hg import -p0 -e "$TESTTMP/foo.patch" -m ignored
applying $TESTTMP/foo.patch
patching file patchdir/f3
Hunk #1 FAILED at 0
1 out of 1 hunks FAILED -- saving rejects to file patchdir/f3.rej
abort: patch failed to apply
[20]
$ hg tracked | grep patchdir
[1]
$ hg files | grep patchdir > /dev/null
[1]
Let's make it apply cleanly and see that it *did* expand properly
$ cat > "$TESTTMP/foo.patch" <<EOF
> --- patchdir/f3
> +++ patchdir/f3
> @@ -1,1 +1,1 @@
> -patch_this
> +patched_this
> EOF
$ PATCHINCLUDES=path:patchdir hg import -p0 -e "$TESTTMP/foo.patch" -m message
applying $TESTTMP/foo.patch
$ cat patchdir/f3
patched_this
$ hg tracked | grep patchdir
I path:patchdir
$ hg files | grep patchdir > /dev/null