manifest: persist the manifestfulltext cache
Reconstructing the manifest from the revlog takes time, so much so that there
already is a LRU cache to avoid having to load a manifest multiple times.
This patch persists that LRU cache in the .hg/cache directory, so we can re-use
this cache across hg commands. Commit benchmark (run on Macos 10.13 on a
2017-model Macbook Pro with Core i7 2.9GHz and flash drive), testing without
and with patch run 5 times, baseline is r2a227782e754:
* committing to an existing file, against the mozilla-central repository.
Baseline real time average 1.9692, with patch 1.3786.
A new debugcommand "hg debugmanifestfulltextcache" lets you inspect the cache,
clear it, or add specific manifest nodeids to it. When calling
repo.updatecaches(), the manifest(s) for the working copy parents are added to
the cache.
The hg perfmanifest command has an additional --clear-disk switch to clear this
cache when testing manifest loading performance.
Using this command to test performance on the firefox repository for revision
f947d902ed91, whose manifest has a delta chain length of 60540, we see:
$ hg perfmanifest f947d902ed91 --clear-disk
! wall 0.972253 comb 0.970000 user 0.850000 sys 0.120000 (best of 10)
$ hg debugmanifestfulltextcache -a `hg log --debug -r f947d902ed91 | grep manifest | cut -d: -f3`
Cache contains 1 manifest entries, in order of most to least recent:
id: 0294517df4aad07c70701db43bc7ff24c3ce7dbc, size 25.6 MB
Total cache data size 25.6 MB, on-disk 0 bytes
$ hg perfmanifest f947d902ed91
! wall 0.036748 comb 0.040000 user 0.020000 sys 0.020000 (best of 100)
Worst-case scenario: a manifest text loaded from a single delta; in the firefox
repository manifest node 9a1246ff762e is the chain base for the manifest
attached to revision f947d902ed91. Loading this from a full cache file is just
as fast as without the cache; the extra node ids ensure a big full cache:
$ for node in 9a1246ff762e 1a1922c14a3e 54a31d11a36a 0294517df4aa; do
> hgd debugmanifestfulltextcache -a $node > /dev/null
> done
$ hgd perfmanifest -m 9a1246ff762e
! wall 0.077513 comb 0.080000 user 0.030000 sys 0.050000 (best of 100)
$ hgd perfmanifest -m 9a1246ff762e --clear-disk
! wall 0.078547 comb 0.080000 user 0.070000 sys 0.010000 (best of 100)
#require unix-permissions
test that new files created in .hg inherit the permissions from .hg/store
$ mkdir dir
just in case somebody has a strange $TMPDIR
$ chmod g-s dir
$ cd dir
$ cat >printmodes.py <<EOF
> from __future__ import absolute_import, print_function
> import os
> import sys
>
> allnames = []
> isdir = {}
> for root, dirs, files in os.walk(sys.argv[1]):
> for d in dirs:
> name = os.path.join(root, d)
> isdir[name] = 1
> allnames.append(name)
> for f in files:
> name = os.path.join(root, f)
> allnames.append(name)
> allnames.sort()
> for name in allnames:
> suffix = name in isdir and '/' or ''
> print('%05o %s%s' % (os.lstat(name).st_mode & 0o7777, name, suffix))
> EOF
$ cat >mode.py <<EOF
> from __future__ import absolute_import, print_function
> import os
> import sys
> print('%05o' % os.lstat(sys.argv[1]).st_mode)
> EOF
$ umask 077
$ hg init repo
$ cd repo
$ chmod 0770 .hg/store
before commit
store can be written by the group, other files cannot
store is setgid
$ $PYTHON ../printmodes.py .
00700 ./.hg/
00600 ./.hg/00changelog.i
00600 ./.hg/requires
00770 ./.hg/store/
$ mkdir dir
$ touch foo dir/bar
$ hg ci -qAm 'add files'
after commit
working dir files can only be written by the owner
files created in .hg can be written by the group
(in particular, store/**, dirstate, branch cache file, undo files)
new directories are setgid
$ $PYTHON ../printmodes.py .
00700 ./.hg/
00600 ./.hg/00changelog.i
00770 ./.hg/cache/
00660 ./.hg/cache/branch2-served
00660 ./.hg/cache/manifestfulltextcache
00660 ./.hg/cache/rbc-names-v1
00660 ./.hg/cache/rbc-revs-v1
00660 ./.hg/dirstate
00660 ./.hg/fsmonitor.state (fsmonitor !)
00660 ./.hg/last-message.txt
00600 ./.hg/requires
00770 ./.hg/store/
00660 ./.hg/store/00changelog.i
00660 ./.hg/store/00manifest.i
00770 ./.hg/store/data/
00770 ./.hg/store/data/dir/
00660 ./.hg/store/data/dir/bar.i (reporevlogstore !)
00660 ./.hg/store/data/foo.i (reporevlogstore !)
00770 ./.hg/store/data/dir/bar/ (reposimplestore !)
00660 ./.hg/store/data/dir/bar/b80de5d138758541c5f05265ad144ab9fa86d1db (reposimplestore !)
00660 ./.hg/store/data/dir/bar/index (reposimplestore !)
00770 ./.hg/store/data/foo/ (reposimplestore !)
00660 ./.hg/store/data/foo/b80de5d138758541c5f05265ad144ab9fa86d1db (reposimplestore !)
00660 ./.hg/store/data/foo/index (reposimplestore !)
00660 ./.hg/store/fncache (repofncache !)
00660 ./.hg/store/phaseroots
00660 ./.hg/store/undo
00660 ./.hg/store/undo.backupfiles
00660 ./.hg/store/undo.phaseroots
00660 ./.hg/undo.backup.dirstate
00660 ./.hg/undo.bookmarks
00660 ./.hg/undo.branch
00660 ./.hg/undo.desc
00660 ./.hg/undo.dirstate
00700 ./dir/
00600 ./dir/bar
00600 ./foo
$ umask 007
$ hg init ../push
before push
group can write everything
$ $PYTHON ../printmodes.py ../push
00770 ../push/.hg/
00660 ../push/.hg/00changelog.i
00660 ../push/.hg/requires
00770 ../push/.hg/store/
$ umask 077
$ hg -q push ../push
after push
group can still write everything
$ $PYTHON ../printmodes.py ../push
00770 ../push/.hg/
00660 ../push/.hg/00changelog.i
00770 ../push/.hg/cache/
00660 ../push/.hg/cache/branch2-base
00660 ../push/.hg/dirstate
00660 ../push/.hg/requires
00770 ../push/.hg/store/
00660 ../push/.hg/store/00changelog.i
00660 ../push/.hg/store/00manifest.i
00770 ../push/.hg/store/data/
00770 ../push/.hg/store/data/dir/
00660 ../push/.hg/store/data/dir/bar.i (reporevlogstore !)
00660 ../push/.hg/store/data/foo.i (reporevlogstore !)
00770 ../push/.hg/store/data/dir/bar/ (reposimplestore !)
00660 ../push/.hg/store/data/dir/bar/b80de5d138758541c5f05265ad144ab9fa86d1db (reposimplestore !)
00660 ../push/.hg/store/data/dir/bar/index (reposimplestore !)
00770 ../push/.hg/store/data/foo/ (reposimplestore !)
00660 ../push/.hg/store/data/foo/b80de5d138758541c5f05265ad144ab9fa86d1db (reposimplestore !)
00660 ../push/.hg/store/data/foo/index (reposimplestore !)
00660 ../push/.hg/store/fncache (repofncache !)
00660 ../push/.hg/store/undo
00660 ../push/.hg/store/undo.backupfiles
00660 ../push/.hg/store/undo.phaseroots
00660 ../push/.hg/undo.bookmarks
00660 ../push/.hg/undo.branch
00660 ../push/.hg/undo.desc
00660 ../push/.hg/undo.dirstate
Test that we don't lose the setgid bit when we call chmod.
Not all systems support setgid directories (e.g. HFS+), so
just check that directories have the same mode.
$ cd ..
$ hg init setgid
$ cd setgid
$ chmod g+rwx .hg/store
$ chmod g+s .hg/store 2> /dev/null || true
$ mkdir dir
$ touch dir/file
$ hg ci -qAm 'add dir/file'
$ storemode=`$PYTHON ../mode.py .hg/store`
$ dirmode=`$PYTHON ../mode.py .hg/store/data/dir`
$ if [ "$storemode" != "$dirmode" ]; then
> echo "$storemode != $dirmode"
> fi
$ cd ..
$ cd .. # g-s dir