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)
$ . "$TESTDIR/narrow-library.sh"
$ hg init master
$ cd master
$ cat >> .hg/hgrc <<EOF
> [narrow]
> serveellipses=True
> EOF
$ mkdir dir
$ mkdir dir/src
$ cd dir/src
$ for x in `$TESTDIR/seq.py 20`; do echo $x > "f$x"; hg add "f$x"; hg commit -m "Commit src $x"; done
$ cd ..
$ mkdir tests
$ cd tests
$ for x in `$TESTDIR/seq.py 20`; do echo $x > "t$x"; hg add "t$x"; hg commit -m "Commit test $x"; done
$ cd ../../..
narrow clone a file, f10
$ hg clone --narrow ssh://user@dummy/master narrow --noupdate --include "dir/src/f10"
requesting all changes
adding changesets
adding manifests
adding file changes
added 3 changesets with 1 changes to 1 files
new changesets *:* (glob)
$ cd narrow
$ cat .hg/requires | grep -v generaldelta
dotencode
fncache
narrowhg-experimental
revlogv1
store
testonly-simplestore (reposimplestore !)
$ cat .hg/narrowspec
[includes]
path:dir/src/f10
[excludes]
$ hg tracked
I path:dir/src/f10
$ hg update
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ find * | sort
dir
dir/src
dir/src/f10
$ cat dir/src/f10
10
$ cd ..
narrow clone with a newline should fail
$ hg clone --narrow ssh://user@dummy/master narrow_fail --noupdate --include 'dir/src/f10
> '
requesting all changes
abort: newlines are not allowed in narrowspec paths
[255]
narrow clone a directory, tests/, except tests/t19
$ hg clone --narrow ssh://user@dummy/master narrowdir --noupdate --include "dir/tests/" --exclude "dir/tests/t19"
requesting all changes
adding changesets
adding manifests
adding file changes
added 21 changesets with 19 changes to 19 files
new changesets *:* (glob)
$ cd narrowdir
$ cat .hg/narrowspec
[includes]
path:dir/tests
[excludes]
path:dir/tests/t19
$ hg tracked
I path:dir/tests
X path:dir/tests/t19
$ hg update
19 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ find * | sort
dir
dir/tests
dir/tests/t1
dir/tests/t10
dir/tests/t11
dir/tests/t12
dir/tests/t13
dir/tests/t14
dir/tests/t15
dir/tests/t16
dir/tests/t17
dir/tests/t18
dir/tests/t2
dir/tests/t20
dir/tests/t3
dir/tests/t4
dir/tests/t5
dir/tests/t6
dir/tests/t7
dir/tests/t8
dir/tests/t9
$ cd ..
narrow clone everything but a directory (tests/)
$ hg clone --narrow ssh://user@dummy/master narrowroot --noupdate --exclude "dir/tests"
requesting all changes
adding changesets
adding manifests
adding file changes
added 21 changesets with 20 changes to 20 files
new changesets *:* (glob)
$ cd narrowroot
$ cat .hg/narrowspec
[includes]
path:.
[excludes]
path:dir/tests
$ hg tracked
I path:.
X path:dir/tests
$ hg update
20 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ find * | sort
dir
dir/src
dir/src/f1
dir/src/f10
dir/src/f11
dir/src/f12
dir/src/f13
dir/src/f14
dir/src/f15
dir/src/f16
dir/src/f17
dir/src/f18
dir/src/f19
dir/src/f2
dir/src/f20
dir/src/f3
dir/src/f4
dir/src/f5
dir/src/f6
dir/src/f7
dir/src/f8
dir/src/f9
$ cd ..
narrow clone no paths at all
$ hg clone --narrow ssh://user@dummy/master narrowempty --noupdate
requesting all changes
adding changesets
adding manifests
adding file changes
added 1 changesets with 0 changes to 0 files
new changesets * (glob)
$ cd narrowempty
$ hg tracked
$ hg update
0 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ ls
$ cd ..
simple clone
$ hg clone ssh://user@dummy/master simpleclone
requesting all changes
adding changesets
adding manifests
adding file changes
added 40 changesets with 40 changes to 40 files
new changesets * (glob)
updating to branch default
40 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ cd simpleclone
$ find * | sort
dir
dir/src
dir/src/f1
dir/src/f10
dir/src/f11
dir/src/f12
dir/src/f13
dir/src/f14
dir/src/f15
dir/src/f16
dir/src/f17
dir/src/f18
dir/src/f19
dir/src/f2
dir/src/f20
dir/src/f3
dir/src/f4
dir/src/f5
dir/src/f6
dir/src/f7
dir/src/f8
dir/src/f9
dir/tests
dir/tests/t1
dir/tests/t10
dir/tests/t11
dir/tests/t12
dir/tests/t13
dir/tests/t14
dir/tests/t15
dir/tests/t16
dir/tests/t17
dir/tests/t18
dir/tests/t19
dir/tests/t2
dir/tests/t20
dir/tests/t3
dir/tests/t4
dir/tests/t5
dir/tests/t6
dir/tests/t7
dir/tests/t8
dir/tests/t9
$ cd ..