Mercurial > hg
view tests/test-issue1175.t @ 42621:99ebde4fec99
commit: improve the files field of changelog for merges
Currently, the files list of merge commits repeats all the deletions
(either actual deletions, or files that got renamed) that happened
between base and p2 of the merge. If p2 is the main branch, the list
can easily be much bigger than the change being merged.
This results in various problems worth improving:
- changelog is bigger than necessary
- `hg log directory` lists many unrelated merge commits, and `hg log
-v -r commit` frequently fills multiple screens worth of files
- it possibly slows down adjustlinkrev, by forcing it to read more
manifests, and that function can certainly be a bottleneck
- the server side of pulls can waste a lot of time simply opening the
filelogs for pointless files (the constant factors for opening even
a tiny filelog is apparently pretty bad)
So stop listing such files as described in the code. Impacted merge
commits and their descendants get a different hash than they would
have without this. This doesn't seem problematic, except for
convert. The previous commit helped with that in the hg->hg case (but
if you do svn->hg twice from scratch, hashes can still change).
The rest of the description is numbers. I don't have much to report,
because recreating the files list of existing repositories is not
easy:
- debugupgradeformat and bundle/unbundle don't recreate the list
- export/import tends to choke quickly applying patches or on
description that contain diffs,
- merge commits from the convert extension don't have the right files
list for reasons orthogonal to the current commit
- replaying the merge with hg update/hg merge/hg revert --all/hg
commit can end up failing in hg revert
- I wasn't sure that using debugsetparents + debugrebuilddirstate
would really build the right thing
I measured commit time before and after this change, in a case with no
files filtered out, several files filtered out (no difference) and 5k
files filtered out (+1% time).
Recreating the 100 more recent merges in a private repo, the
concatenated uncompressed files lists goes from 1.12MB to
0.52MB. Excluding 3 merges that are not representative, then the size
goes from 570k to 15k.
I converted part of mozilla-central, and observed file list shrinking
quite a bit too, starting at the very first merge, 733641d9feaf, going
from 550 files to 10 files (although they have relatively few merges,
so they probably wouldn't care).
Differential Revision: https://phab.mercurial-scm.org/D6613
author | Valentin Gatien-Baron <valentin.gatienbaron@gmail.com> |
---|---|
date | Tue, 02 Jul 2019 12:59:58 -0400 |
parents | 3a7efcbdf288 |
children | 3df0bd706c40 |
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https://bz.mercurial-scm.org/1175 $ hg init $ touch a $ hg ci -Am0 adding a $ hg mv a a1 $ hg ci -m1 $ hg co 0 1 files updated, 0 files merged, 1 files removed, 0 files unresolved $ hg mv a a2 $ hg up note: possible conflict - a was renamed multiple times to: a1 a2 1 files updated, 0 files merged, 0 files removed, 0 files unresolved $ hg ci -m2 $ touch a $ hg ci -Am3 adding a $ hg mv a b $ hg ci -Am4 a $ hg ci --debug --traceback -Am5 b committing files: b warning: can't find ancestor for 'b' copied from 'a'! committing manifest committing changelog updating the branch cache committed changeset 5:83a687e8a97c80992ba385bbfd766be181bfb1d1 $ hg verify checking changesets checking manifests crosschecking files in changesets and manifests checking files checked 6 changesets with 4 changes to 4 files $ hg export --git tip # HG changeset patch # User test # Date 0 0 # Thu Jan 01 00:00:00 1970 +0000 # Node ID 83a687e8a97c80992ba385bbfd766be181bfb1d1 # Parent 1d1625283f71954f21d14c3d44d0ad3c019c597f 5 diff --git a/b b/b new file mode 100644 https://bz.mercurial-scm.org/show_bug.cgi?id=4476 $ hg init foo $ cd foo $ touch a && hg ci -Aqm a $ hg mv a b $ echo b1 >> b $ hg ci -Aqm b1 $ hg up 0 1 files updated, 0 files merged, 1 files removed, 0 files unresolved $ hg mv a b $ echo b2 >> b $ hg ci -Aqm b2 $ hg graft 1 grafting 1:5974126fad84 "b1" merging b warning: conflicts while merging b! (edit, then use 'hg resolve --mark') abort: unresolved conflicts, can't continue (use 'hg resolve' and 'hg graft --continue') [255] $ echo a > b $ echo b3 >> b $ hg resolve --mark b (no more unresolved files) continue: hg graft --continue $ hg graft --continue grafting 1:5974126fad84 "b1" warning: can't find ancestor for 'b' copied from 'a'! $ hg log -f b -T 'changeset: {rev}:{node|short}\nsummary: {desc}\n\n' changeset: 3:376d30ccffc0 summary: b1 changeset: 2:416baaa2e5e4 summary: b2 changeset: 0:3903775176ed summary: a