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)
test for old histedit issue #6:
editing a changeset without any actual change would corrupt the repository
$ . "$TESTDIR/histedit-helpers.sh"
$ cat >> $HGRCPATH <<EOF
> [extensions]
> histedit=
> EOF
$ initrepo ()
> {
> dir="$1"
> comment="$2"
> if [ -n "${comment}" ]; then
> echo % ${comment}
> echo % ${comment} | sed 's:.:-:g'
> fi
> hg init ${dir}
> cd ${dir}
> for x in a b c d e f ; do
> echo $x > $x
> hg add $x
> hg ci -m $x
> done
> cd ..
> }
$ geneditor ()
> {
> # generate an editor script for selecting changesets to be edited
> choice=$1 # changesets that should be edited (using sed line ranges)
> cat <<EOF | sed 's:^....::'
> # editing the rules, replacing 'pick' with 'edit' for the chosen lines
> sed '${choice}s:^pick:edit:' "\$1" > "\${1}.tmp"
> mv "\${1}.tmp" "\$1"
> # displaying the resulting rules, minus comments and empty lines
> sed '/^#/d;/^$/d;s:^:| :' "\$1" >&2
> EOF
> }
$ startediting ()
> {
> # begin an editing session
> choice="$1" # changesets that should be edited
> number="$2" # number of changesets considered (from tip)
> comment="$3"
> geneditor "${choice}" > edit.sh
> echo % start editing the history ${comment}
> HGEDITOR="sh ./edit.sh" hg histedit -- -${number} 2>&1 | fixbundle
> }
$ continueediting ()
> {
> # continue an edit already in progress
> editor="$1" # message editor when finalizing editing
> comment="$2"
> echo % finalize changeset editing ${comment}
> HGEDITOR=${editor} hg histedit --continue 2>&1 | fixbundle
> }
$ graphlog ()
> {
> comment="${1:-log}"
> echo % "${comment}"
> hg log -G --template '{rev} {node} \"{desc|firstline}\"\n'
> }
$ initrepo r1 "test editing with no change"
% test editing with no change
-----------------------------
$ cd r1
$ graphlog "log before editing"
% log before editing
@ 5 652413bf663ef2a641cab26574e46d5f5a64a55a "f"
|
o 4 e860deea161a2f77de56603b340ebbb4536308ae "e"
|
o 3 055a42cdd88768532f9cf79daa407fc8d138de9b "d"
|
o 2 177f92b773850b59254aa5e923436f921b55483b "c"
|
o 1 d2ae7f538514cd87c17547b0de4cea71fe1af9fb "b"
|
o 0 cb9a9f314b8b07ba71012fcdbc544b5a4d82ff5b "a"
$ startediting 2 3 "(not changing anything)" # edit the 2nd of 3 changesets
% start editing the history (not changing anything)
| pick 055a42cdd887 3 d
| edit e860deea161a 4 e
| pick 652413bf663e 5 f
0 files updated, 0 files merged, 2 files removed, 0 files unresolved
Editing (e860deea161a), commit as needed now to split the change
(to edit e860deea161a, `hg histedit --continue` after making changes)
$ continueediting true "(leaving commit message unaltered)"
% finalize changeset editing (leaving commit message unaltered)
check state of working copy
$ hg id
794fe033d0a0 tip
$ graphlog "log after history editing"
% log after history editing
@ 5 794fe033d0a030f8df77c5de945fca35c9181c30 "f"
|
o 4 04d2fab980779f332dec458cc944f28de8b43435 "e"
|
o 3 055a42cdd88768532f9cf79daa407fc8d138de9b "d"
|
o 2 177f92b773850b59254aa5e923436f921b55483b "c"
|
o 1 d2ae7f538514cd87c17547b0de4cea71fe1af9fb "b"
|
o 0 cb9a9f314b8b07ba71012fcdbc544b5a4d82ff5b "a"
$ cd ..
$ initrepo r2 "test editing with no change, then abort"
% test editing with no change, then abort
-----------------------------------------
$ cd r2
$ graphlog "log before editing"
% log before editing
@ 5 652413bf663ef2a641cab26574e46d5f5a64a55a "f"
|
o 4 e860deea161a2f77de56603b340ebbb4536308ae "e"
|
o 3 055a42cdd88768532f9cf79daa407fc8d138de9b "d"
|
o 2 177f92b773850b59254aa5e923436f921b55483b "c"
|
o 1 d2ae7f538514cd87c17547b0de4cea71fe1af9fb "b"
|
o 0 cb9a9f314b8b07ba71012fcdbc544b5a4d82ff5b "a"
$ startediting 1,2 3 "(not changing anything)" # edit the 1st two of 3 changesets
% start editing the history (not changing anything)
| edit 055a42cdd887 3 d
| edit e860deea161a 4 e
| pick 652413bf663e 5 f
0 files updated, 0 files merged, 3 files removed, 0 files unresolved
Editing (055a42cdd887), commit as needed now to split the change
(to edit 055a42cdd887, `hg histedit --continue` after making changes)
$ continueediting true "(leaving commit message unaltered)"
% finalize changeset editing (leaving commit message unaltered)
Editing (e860deea161a), commit as needed now to split the change
(to edit e860deea161a, `hg histedit --continue` after making changes)
$ graphlog "log after first edit"
% log after first edit
@ 6 e5ae3ca2f1ffdbd89ec41ebc273a231f7c3022f2 "d"
|
| o 5 652413bf663ef2a641cab26574e46d5f5a64a55a "f"
| |
| o 4 e860deea161a2f77de56603b340ebbb4536308ae "e"
| |
| o 3 055a42cdd88768532f9cf79daa407fc8d138de9b "d"
|/
o 2 177f92b773850b59254aa5e923436f921b55483b "c"
|
o 1 d2ae7f538514cd87c17547b0de4cea71fe1af9fb "b"
|
o 0 cb9a9f314b8b07ba71012fcdbc544b5a4d82ff5b "a"
abort editing session, after first forcibly updating away
$ hg up 0
abort: histedit in progress
(use 'hg histedit --continue' or 'hg histedit --abort')
[20]
$ mv .hg/histedit-state .hg/histedit-state-ignore
$ hg up 0
0 files updated, 0 files merged, 3 files removed, 0 files unresolved
$ mv .hg/histedit-state-ignore .hg/histedit-state
$ hg sum
parent: 0:cb9a9f314b8b
a
branch: default
commit: 1 added, 1 unknown (new branch head)
update: 6 new changesets (update)
phases: 7 draft
hist: 2 remaining (histedit --continue)
$ hg histedit --abort 2>&1 | fixbundle
modified files should survive the abort when we've moved away already
$ hg st
A e
? edit.sh
$ graphlog "log after abort"
% log after abort
o 5 652413bf663ef2a641cab26574e46d5f5a64a55a "f"
|
o 4 e860deea161a2f77de56603b340ebbb4536308ae "e"
|
o 3 055a42cdd88768532f9cf79daa407fc8d138de9b "d"
|
o 2 177f92b773850b59254aa5e923436f921b55483b "c"
|
o 1 d2ae7f538514cd87c17547b0de4cea71fe1af9fb "b"
|
@ 0 cb9a9f314b8b07ba71012fcdbc544b5a4d82ff5b "a"
aborting and not changing files can skip mentioning updating (no) files
$ hg up
5 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg commit --close-branch -m 'closebranch'
$ startediting 1 1 "(not changing anything)" # edit the 3rd of 3 changesets
% start editing the history (not changing anything)
| edit 292aec348d9e 6 closebranch
Editing (292aec348d9e), commit as needed now to split the change
(to edit 292aec348d9e, `hg histedit --continue` after making changes)
$ hg histedit --abort
$ cd ..