Mercurial > hg
view tests/test-rebase-newancestor.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 | 4764e8436b2a |
children | 77bb38be00ea |
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$ cat >> $HGRCPATH <<EOF > [extensions] > rebase= > drawdag=$TESTDIR/drawdag.py > [alias] > tglog = log -G --template "{rev}: {node|short} '{desc}' {branches}\n" > EOF $ hg init repo $ cd repo $ echo A > a $ echo >> a $ hg ci -Am A adding a $ echo B > a $ echo >> a $ hg ci -m B $ echo C > a $ echo >> a $ hg ci -m C $ hg up -q -C 0 $ echo D >> a $ hg ci -Am AD created new head $ hg tglog @ 3: 3878212183bd 'AD' | | o 2: 30ae917c0e4f 'C' | | | o 1: 0f4f7cb4f549 'B' |/ o 0: 1e635d440a73 'A' $ hg rebase -s 1 -d 3 rebasing 1:0f4f7cb4f549 "B" merging a rebasing 2:30ae917c0e4f "C" merging a saved backup bundle to $TESTTMP/repo/.hg/strip-backup/0f4f7cb4f549-82b3b163-rebase.hg $ hg tglog o 3: 25773bc4b4b0 'C' | o 2: c09015405f75 'B' | @ 1: 3878212183bd 'AD' | o 0: 1e635d440a73 'A' $ cd .. Test rebasing of merges with ancestors of the rebase destination - a situation that often happens when trying to recover from repeated merging with a mainline branch. The test case creates a dev branch that contains a couple of merges from the default branch. When rebasing to the default branch, these merges would be merges with ancestors on the same branch. The merges _could_ contain some interesting conflict resolutions or additional changes in the merge commit, but that is mixed up with the actual merge stuff and there is in general no way to separate them. Note: The dev branch contains _no_ changes to f-default. It might be unclear how rebasing of ancestor merges should be handled, but the current behavior with spurious prompts for conflicts in files that didn't change seems very wrong. $ hg init ancestor-merge $ cd ancestor-merge $ touch f-default $ hg ci -Aqm 'default: create f-default' $ hg branch -q dev $ hg ci -qm 'dev: create branch' $ echo stuff > f-dev $ hg ci -Aqm 'dev: f-dev stuff' $ hg up -q default $ echo stuff > f-default $ hg ci -m 'default: f-default stuff' $ hg up -q dev $ hg merge -q default $ hg ci -m 'dev: merge default' $ hg up -q default $ hg rm f-default $ hg ci -m 'default: remove f-default' $ hg up -q dev $ hg merge -q default $ hg ci -m 'dev: merge default' $ hg up -q default $ echo stuff > f-other $ hg ci -Aqm 'default: f-other stuff' $ hg tglog @ 7: e08089805d82 'default: f-other stuff' | | o 6: 010ced67e558 'dev: merge default' dev |/| o | 5: 462860db70a1 'default: remove f-default' | | | o 4: 4b019212aaf6 'dev: merge default' dev |/| o | 3: f157ecfd2b6b 'default: f-default stuff' | | | o 2: ec2c14fb2984 'dev: f-dev stuff' dev | | | o 1: 1d1a643d390e 'dev: create branch' dev |/ o 0: e90e8eb90b6f 'default: create f-default' $ hg clone -qU . ../ancestor-merge-2 Full rebase all the way back from branching point: $ hg rebase -r 'only(dev,default)' -d default --config ui.interactive=True << EOF > c > EOF rebasing 1:1d1a643d390e "dev: create branch" note: not rebasing 1:1d1a643d390e "dev: create branch", its destination already has all its changes rebasing 2:ec2c14fb2984 "dev: f-dev stuff" rebasing 4:4b019212aaf6 "dev: merge default" file 'f-default' was deleted in local [dest] but was modified in other [source]. You can use (c)hanged version, leave (d)eleted, or leave (u)nresolved. What do you want to do? c rebasing 6:010ced67e558 "dev: merge default" saved backup bundle to $TESTTMP/ancestor-merge/.hg/strip-backup/1d1a643d390e-4a6f6d17-rebase.hg $ hg tglog o 6: de147e4f69cf 'dev: merge default' | o 5: eda7b7f46f5d 'dev: merge default' | o 4: 3e075b1c0a40 'dev: f-dev stuff' | @ 3: e08089805d82 'default: f-other stuff' | o 2: 462860db70a1 'default: remove f-default' | o 1: f157ecfd2b6b 'default: f-default stuff' | o 0: e90e8eb90b6f 'default: create f-default' Grafty cherry picking rebasing: $ cd ../ancestor-merge-2 $ hg phase -fdr0: $ hg rebase -r 'children(only(dev,default))' -d default --config ui.interactive=True << EOF > c > EOF rebasing 2:ec2c14fb2984 "dev: f-dev stuff" rebasing 4:4b019212aaf6 "dev: merge default" file 'f-default' was deleted in local [dest] but was modified in other [source]. You can use (c)hanged version, leave (d)eleted, or leave (u)nresolved. What do you want to do? c rebasing 6:010ced67e558 "dev: merge default" saved backup bundle to $TESTTMP/ancestor-merge-2/.hg/strip-backup/ec2c14fb2984-827d7a44-rebase.hg $ hg tglog o 7: de147e4f69cf 'dev: merge default' | o 6: eda7b7f46f5d 'dev: merge default' | o 5: 3e075b1c0a40 'dev: f-dev stuff' | o 4: e08089805d82 'default: f-other stuff' | o 3: 462860db70a1 'default: remove f-default' | o 2: f157ecfd2b6b 'default: f-default stuff' | | o 1: 1d1a643d390e 'dev: create branch' dev |/ o 0: e90e8eb90b6f 'default: create f-default' $ cd .. Test order of parents of rebased merged with un-rebased changes as p1. $ hg init parentorder $ cd parentorder $ touch f $ hg ci -Aqm common $ touch change $ hg ci -Aqm change $ touch target $ hg ci -Aqm target $ hg up -qr 0 $ touch outside $ hg ci -Aqm outside $ hg merge -qr 1 $ hg ci -m 'merge p1 3=outside p2 1=ancestor' $ hg par changeset: 4:6990226659be tag: tip parent: 3:f59da8fc0fcf parent: 1:dd40c13f7a6f user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: merge p1 3=outside p2 1=ancestor $ hg up -qr 1 $ hg merge -qr 3 $ hg ci -qm 'merge p1 1=ancestor p2 3=outside' $ hg par changeset: 5:a57575f79074 tag: tip parent: 1:dd40c13f7a6f parent: 3:f59da8fc0fcf user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: merge p1 1=ancestor p2 3=outside $ hg tglog @ 5: a57575f79074 'merge p1 1=ancestor p2 3=outside' |\ +---o 4: 6990226659be 'merge p1 3=outside p2 1=ancestor' | |/ | o 3: f59da8fc0fcf 'outside' | | +---o 2: a60552eb93fb 'target' | | o | 1: dd40c13f7a6f 'change' |/ o 0: 02f0f58d5300 'common' $ hg rebase -r 4 -d 2 rebasing 4:6990226659be "merge p1 3=outside p2 1=ancestor" saved backup bundle to $TESTTMP/parentorder/.hg/strip-backup/6990226659be-4d67a0d3-rebase.hg $ hg tip changeset: 5:cca50676b1c5 tag: tip parent: 2:a60552eb93fb parent: 3:f59da8fc0fcf user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: merge p1 3=outside p2 1=ancestor $ hg rebase -r 4 -d 2 rebasing 4:a57575f79074 "merge p1 1=ancestor p2 3=outside" saved backup bundle to $TESTTMP/parentorder/.hg/strip-backup/a57575f79074-385426e5-rebase.hg $ hg tip changeset: 5:f9daf77ffe76 tag: tip parent: 2:a60552eb93fb parent: 3:f59da8fc0fcf user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: merge p1 1=ancestor p2 3=outside $ hg tglog @ 5: f9daf77ffe76 'merge p1 1=ancestor p2 3=outside' |\ +---o 4: cca50676b1c5 'merge p1 3=outside p2 1=ancestor' | |/ | o 3: f59da8fc0fcf 'outside' | | o | 2: a60552eb93fb 'target' | | o | 1: dd40c13f7a6f 'change' |/ o 0: 02f0f58d5300 'common' rebase of merge of ancestors $ hg up -qr 2 $ hg merge -qr 3 $ echo 'other change while merging future "rebase ancestors"' > other $ hg ci -Aqm 'merge rebase ancestors' $ hg rebase -d 5 -v rebasing 6:4c5f12f25ebe "merge rebase ancestors" (tip) resolving manifests removing other note: merging f9daf77ffe76+ and 4c5f12f25ebe using bids from ancestors a60552eb93fb and f59da8fc0fcf calculating bids for ancestor a60552eb93fb resolving manifests calculating bids for ancestor f59da8fc0fcf resolving manifests auction for merging merge bids other: consensus for g end of auction getting other committing files: other committing manifest committing changelog rebase merging completed 1 changesets found uncompressed size of bundle content: 199 (changelog) 216 (manifests) 182 other saved backup bundle to $TESTTMP/parentorder/.hg/strip-backup/4c5f12f25ebe-f46990e5-rebase.hg 1 changesets found uncompressed size of bundle content: 254 (changelog) 167 (manifests) 182 other adding branch adding changesets adding manifests adding file changes added 1 changesets with 1 changes to 1 files rebase completed $ hg tglog @ 6: 113755df812b 'merge rebase ancestors' | o 5: f9daf77ffe76 'merge p1 1=ancestor p2 3=outside' |\ +---o 4: cca50676b1c5 'merge p1 3=outside p2 1=ancestor' | |/ | o 3: f59da8fc0fcf 'outside' | | o | 2: a60552eb93fb 'target' | | o | 1: dd40c13f7a6f 'change' |/ o 0: 02f0f58d5300 'common' Due to the limitation of 3-way merge algorithm (1 merge base), rebasing a merge may include unwanted content: $ hg init $TESTTMP/dual-merge-base1 $ cd $TESTTMP/dual-merge-base1 $ hg debugdrawdag <<'EOS' > F > /| > D E > | | > B C > |/ > A Z > |/ > R > EOS $ hg rebase -r D+E+F -d Z rebasing 5:5f2c926dfecf "D" (D) rebasing 6:b296604d9846 "E" (E) rebasing 7:caa9781e507d "F" (F tip) abort: rebasing 7:caa9781e507d will include unwanted changes from 4:d6003a550c2c or 3:c1e6b162678d [255] The warning does not get printed if there is no unwanted change detected: $ hg init $TESTTMP/dual-merge-base2 $ cd $TESTTMP/dual-merge-base2 $ hg debugdrawdag <<'EOS' > D > /| > B C > |/ > A Z > |/ > R > EOS $ hg rebase -r B+C+D -d Z rebasing 3:c1e6b162678d "B" (B) rebasing 4:d6003a550c2c "C" (C) rebasing 5:c8f78076273e "D" (D tip) saved backup bundle to $TESTTMP/dual-merge-base2/.hg/strip-backup/d6003a550c2c-6f1424b6-rebase.hg $ hg manifest -r 'desc(D)' B C R Z The merge base could be different from old p1 (changed parent becomes new p1): $ hg init $TESTTMP/chosen-merge-base1 $ cd $TESTTMP/chosen-merge-base1 $ hg debugdrawdag <<'EOS' > F > /| > D E > | | > B C Z > EOS $ hg rebase -r D+F -d Z rebasing 3:004dc1679908 "D" (D) rebasing 5:4be4cbf6f206 "F" (F tip) saved backup bundle to $TESTTMP/chosen-merge-base1/.hg/strip-backup/004dc1679908-06a66a3c-rebase.hg $ hg manifest -r 'desc(F)' C D E Z $ hg log -r `hg log -r 'desc(F)' -T '{p1node}'` -T '{desc}\n' D $ hg init $TESTTMP/chosen-merge-base2 $ cd $TESTTMP/chosen-merge-base2 $ hg debugdrawdag <<'EOS' > F > /| > D E > | | > B C Z > EOS $ hg rebase -r E+F -d Z rebasing 4:974e4943c210 "E" (E) rebasing 5:4be4cbf6f206 "F" (F tip) saved backup bundle to $TESTTMP/chosen-merge-base2/.hg/strip-backup/974e4943c210-b2874da5-rebase.hg $ hg manifest -r 'desc(F)' B D E Z $ hg log -r `hg log -r 'desc(F)' -T '{p1node}'` -T '{desc}\n' E