stream-clone: avoid opening a revlog in case we do not need it
Opening an revlog has a cost, especially if it is inline as we have to scan the
file and construct an index.
To prevent the associated slowdown, we just do a minimal scan to check that an
inline file is still inline, and simply stream the file without creating a
revlog when we can.
This provides a big boost compared to the previous changeset, even if the full
generation is still penalized by the initial gathering of information.
All benchmarks are run on linux with Python 3.10.7.
# benchmark.name = hg.exchange.stream.generate
# benchmark.variants.version = v2
### Compared to the previous changesets
We get a large win all across the board!
# mercurial-2018-08-01-zstd-sparse-revlog
before: 0.250694 seconds
after: 0.105986 seconds (-57.72%)
# pypy-2018-08-01-zstd-sparse-revlog
before: 3.885657 seconds
after: 1.709748 seconds (-56.00%)
# netbeans-2018-08-01-zstd-sparse-revlog
before: 16.679371 seconds
after: 7.687469 seconds (-53.91%)
# mozilla-central-2018-08-01-zstd-sparse-revlog
before: 38.575482 seconds
after: 17.520316 seconds (-54.58%)
# mozilla-try-2019-02-18-zstd-sparse-revlog
before: 81.160994 seconds
after: 37.073753 seconds (-54.32%)
### Compared to 6.4.3
We are still significantly slower than 6.4.3, the extra time is usually twice
slower than the extra time we observe on the locked section, which is a quite
interesting information.
Except for mercurial-central that is much faster. That discrepancy is not really
explained yet.
# mercurial-2018-08-01-zstd-sparse-revlog
6.4.3: 0.072560 seconds
after: 0.105986 seconds (+46.07%) (- 0.03 seconds)
# pypy-2018-08-01-zstd-sparse-revlog
6.4.3: 1.211193 seconds
after: 1.709748 seconds (+41.16%) (-0.45 seconds)
# netbeans-2018-08-01-zstd-sparse-revlog
6.4.3: 4.932843 seconds
after: 7.687469 seconds (+55.84%) (-2.75 seconds)
# mozilla-central-2018-08-01-zstd-sparse-revlog
6.4.3: 34.012226 seconds
after: 17.520316 seconds (-48.49%) (-16.49 seconds)
# mozilla-try-2019-02-18-zstd-sparse-revlog
6.4.3: 23.850555 seconds
after: 37.073753 seconds (+55.44%) (+13.22 seconds)
$ . "$TESTDIR/histedit-helpers.sh"
$ cat >> $HGRCPATH <<EOF
> [extensions]
> histedit=
> EOF
$ modwithdate ()
> {
> echo $1 > $1
> hg ci -m $1 -d "$2 0"
> }
$ initrepo ()
> {
> hg init $1
> cd $1
> for x in a b c d e f ; do
> echo $x$x$x$x$x > $x
> hg add $x
> done
> hg ci -m 'Initial commit'
> modwithdate a 1
> modwithdate b 2
> modwithdate c 3
> modwithdate d 4
> modwithdate e 5
> modwithdate f 6
> echo 'I can haz no commute' > e
> hg ci -m 'does not commute with e' -d '7 0'
> cd ..
> }
$ initrepo r
$ cd r
Initial generation of the command files
$ EDITED="$TESTTMP/editedhistory"
$ hg log --template 'pick {node|short} {rev} {desc}\n' -r 3 >> $EDITED
$ hg log --template 'pick {node|short} {rev} {desc}\n' -r 4 >> $EDITED
$ hg log --template 'fold {node|short} {rev} {desc}\n' -r 7 >> $EDITED
$ hg log --template 'pick {node|short} {rev} {desc}\n' -r 5 >> $EDITED
$ hg log --template 'pick {node|short} {rev} {desc}\n' -r 6 >> $EDITED
$ cat $EDITED
pick 092e4ce14829 3 c
pick ae78f4c9d74f 4 d
fold 42abbb61bede 7 does not commute with e
pick 7f3755409b00 5 e
pick dd184f2faeb0 6 f
log before edit
$ hg log --graph
@ changeset: 7:42abbb61bede
| tag: tip
| user: test
| date: Thu Jan 01 00:00:07 1970 +0000
| summary: does not commute with e
|
o changeset: 6:dd184f2faeb0
| user: test
| date: Thu Jan 01 00:00:06 1970 +0000
| summary: f
|
o changeset: 5:7f3755409b00
| user: test
| date: Thu Jan 01 00:00:05 1970 +0000
| summary: e
|
o changeset: 4:ae78f4c9d74f
| user: test
| date: Thu Jan 01 00:00:04 1970 +0000
| summary: d
|
o changeset: 3:092e4ce14829
| user: test
| date: Thu Jan 01 00:00:03 1970 +0000
| summary: c
|
o changeset: 2:40ccdd8beb95
| user: test
| date: Thu Jan 01 00:00:02 1970 +0000
| summary: b
|
o changeset: 1:cd997a145b29
| user: test
| date: Thu Jan 01 00:00:01 1970 +0000
| summary: a
|
o changeset: 0:1715188a53c7
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: Initial commit
edit the history
$ hg histedit 3 --commands $EDITED 2>&1 | fixbundle
merging e
warning: conflicts while merging e! (edit, then use 'hg resolve --mark')
Fix up the change (fold 42abbb61bede)
(hg histedit --continue to resume)
fix up
$ echo 'I can haz no commute' > e
$ hg resolve --mark e
(no more unresolved files)
continue: hg histedit --continue
$ HGEDITOR=cat hg histedit --continue 2>&1 | fixbundle | grep -v '2 files removed'
d
***
does not commute with e
HG: Enter commit message. Lines beginning with 'HG:' are removed.
HG: Leave message empty to abort commit.
HG: --
HG: user: test
HG: branch 'default'
HG: changed d
HG: changed e
merging e
warning: conflicts while merging e! (edit, then use 'hg resolve --mark')
Fix up the change (pick 7f3755409b00)
(hg histedit --continue to resume)
just continue this time
keep the non-commuting change, and thus the pending change will be dropped
$ hg revert -r 'p1()' e
$ hg resolve --mark e
(no more unresolved files)
continue: hg histedit --continue
$ hg diff
$ hg histedit --continue 2>&1 | fixbundle
7f3755409b00: skipping changeset (no changes)
log after edit
$ hg log --graph
@ changeset: 5:1300355b1a54
| tag: tip
| user: test
| date: Thu Jan 01 00:00:06 1970 +0000
| summary: f
|
o changeset: 4:e2ac33269083
| user: test
| date: Thu Jan 01 00:00:07 1970 +0000
| summary: d
|
o changeset: 3:092e4ce14829
| user: test
| date: Thu Jan 01 00:00:03 1970 +0000
| summary: c
|
o changeset: 2:40ccdd8beb95
| user: test
| date: Thu Jan 01 00:00:02 1970 +0000
| summary: b
|
o changeset: 1:cd997a145b29
| user: test
| date: Thu Jan 01 00:00:01 1970 +0000
| summary: a
|
o changeset: 0:1715188a53c7
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: Initial commit
contents of e
$ hg cat e
I can haz no commute
manifest
$ hg manifest
a
b
c
d
e
f
$ cd ..
Repeat test using "roll", not "fold". "roll" folds in changes but drops message and date
$ initrepo r2
$ cd r2
Initial generation of the command files
$ EDITED="$TESTTMP/editedhistory.2"
$ hg log --template 'pick {node|short} {rev} {desc}\n' -r 3 >> $EDITED
$ hg log --template 'pick {node|short} {rev} {desc}\n' -r 4 >> $EDITED
$ hg log --template 'roll {node|short} {rev} {desc}\n' -r 7 >> $EDITED
$ hg log --template 'pick {node|short} {rev} {desc}\n' -r 5 >> $EDITED
$ hg log --template 'pick {node|short} {rev} {desc}\n' -r 6 >> $EDITED
$ cat $EDITED
pick 092e4ce14829 3 c
pick ae78f4c9d74f 4 d
roll 42abbb61bede 7 does not commute with e
pick 7f3755409b00 5 e
pick dd184f2faeb0 6 f
log before edit
$ hg log --graph
@ changeset: 7:42abbb61bede
| tag: tip
| user: test
| date: Thu Jan 01 00:00:07 1970 +0000
| summary: does not commute with e
|
o changeset: 6:dd184f2faeb0
| user: test
| date: Thu Jan 01 00:00:06 1970 +0000
| summary: f
|
o changeset: 5:7f3755409b00
| user: test
| date: Thu Jan 01 00:00:05 1970 +0000
| summary: e
|
o changeset: 4:ae78f4c9d74f
| user: test
| date: Thu Jan 01 00:00:04 1970 +0000
| summary: d
|
o changeset: 3:092e4ce14829
| user: test
| date: Thu Jan 01 00:00:03 1970 +0000
| summary: c
|
o changeset: 2:40ccdd8beb95
| user: test
| date: Thu Jan 01 00:00:02 1970 +0000
| summary: b
|
o changeset: 1:cd997a145b29
| user: test
| date: Thu Jan 01 00:00:01 1970 +0000
| summary: a
|
o changeset: 0:1715188a53c7
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: Initial commit
edit the history
$ hg histedit 3 --commands $EDITED 2>&1 | fixbundle
merging e
warning: conflicts while merging e! (edit, then use 'hg resolve --mark')
Fix up the change (roll 42abbb61bede)
(hg histedit --continue to resume)
fix up
$ echo 'I can haz no commute' > e
$ hg resolve --mark e
(no more unresolved files)
continue: hg histedit --continue
$ hg histedit --continue 2>&1 | fixbundle | grep -v '2 files removed'
merging e
warning: conflicts while merging e! (edit, then use 'hg resolve --mark')
Fix up the change (pick 7f3755409b00)
(hg histedit --continue to resume)
just continue this time
$ hg revert -r 'p1()' e
$ hg resolve --mark e
(no more unresolved files)
continue: hg histedit --continue
$ hg histedit --continue 2>&1 | fixbundle
7f3755409b00: skipping changeset (no changes)
log after edit
$ hg log --graph
@ changeset: 5:b538bcb461be
| tag: tip
| user: test
| date: Thu Jan 01 00:00:06 1970 +0000
| summary: f
|
o changeset: 4:317e37cb6d66
| user: test
| date: Thu Jan 01 00:00:04 1970 +0000
| summary: d
|
o changeset: 3:092e4ce14829
| user: test
| date: Thu Jan 01 00:00:03 1970 +0000
| summary: c
|
o changeset: 2:40ccdd8beb95
| user: test
| date: Thu Jan 01 00:00:02 1970 +0000
| summary: b
|
o changeset: 1:cd997a145b29
| user: test
| date: Thu Jan 01 00:00:01 1970 +0000
| summary: a
|
o changeset: 0:1715188a53c7
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: Initial commit
contents of e
$ hg cat e
I can haz no commute
manifest
$ hg manifest
a
b
c
d
e
f
description is taken from rollup target commit
$ hg log --debug --rev 4
changeset: 4:317e37cb6d66c1c84628c00e5bf4c8c292831951
phase: draft
parent: 3:092e4ce14829f4974399ce4316d59f64ef0b6725
parent: -1:0000000000000000000000000000000000000000
manifest: 4:b068a323d969f22af1296ec6a5ea9384cef437ac
user: test
date: Thu Jan 01 00:00:04 1970 +0000
files: d e
extra: branch=default
extra: histedit_source=ae78f4c9d74ffa4b6cb5045001c303fe9204e890,42abbb61bede6f4366fa1e74a664343e5d558a70
description:
d
done with repo r2
$ cd ..