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
#require no-windows
$ . "$TESTDIR/remotefilelog-library.sh"
$ hg init master
$ cd master
$ cat >> .hg/hgrc <<EOF
> [remotefilelog]
> server=True
> EOF
$ echo x > x
$ hg commit -qAm x
$ cd ..
$ hgcloneshallow ssh://user@dummy/master shallow -q
1 files fetched over 1 fetches - (1 misses, 0.00% hit ratio) over *s (glob)
$ hgcloneshallow ssh://user@dummy/master shallow2 -q
We should see the remotefilelog capability here, which advertises that
the server supports our custom getfiles method.
$ cd master
$ echo 'hello' | hg -R . serve --stdio | grep capa | identifyrflcaps
exp-remotefilelog-ssh-getfiles-1
x_rfl_getfile
x_rfl_getflogheads
$ echo 'capabilities' | hg -R . serve --stdio | identifyrflcaps ; echo
exp-remotefilelog-ssh-getfiles-1
x_rfl_getfile
x_rfl_getflogheads
# pull to shallow from full
$ echo y > y
$ hg commit -qAm y
$ cd ../shallow
$ hg pull
pulling from ssh://user@dummy/master
searching for changes
adding changesets
adding manifests
adding file changes
added 1 changesets with 0 changes to 0 files
new changesets d34c38483be9
(run 'hg update' to get a working copy)
$ hg up
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
1 files fetched over 1 fetches - (1 misses, 0.00% hit ratio) over *s (glob)
$ cat y
y
$ cd ..
# pull from shallow to shallow (local)
$ cd shallow
$ echo z > z
$ hg commit -qAm z
$ echo x >> x
$ echo y >> y
$ hg commit -qAm xxyy
$ cd ../shallow2
$ clearcache
$ hg pull ../shallow
pulling from ../shallow
searching for changes
adding changesets
adding manifests
adding file changes
added 3 changesets with 4 changes to 3 files
new changesets d34c38483be9:d7373980d475 (2 drafts)
(run 'hg update' to get a working copy)
2 files fetched over 2 fetches - (2 misses, 0.00% hit ratio) over *s (glob)
# pull from shallow to shallow (ssh)
$ hg strip -r 1
saved backup bundle to $TESTTMP/shallow2/.hg/strip-backup/d34c38483be9-89d325c9-backup.hg (glob)
$ hg pull ssh://user@dummy/$TESTTMP/shallow --config remotefilelog.cachepath=${CACHEDIR}2
pulling from ssh://user@dummy/$TESTTMP/shallow
searching for changes
adding changesets
adding manifests
adding file changes
added 3 changesets with 4 changes to 3 files
new changesets d34c38483be9:d7373980d475 (2 drafts)
(run 'hg update' to get a working copy)
1 files fetched over 1 fetches - (1 misses, 0.00% hit ratio) over *s (glob)
$ hg up
3 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ cat z
z
$ hg -R ../shallow strip -qr 3
$ hg strip -qr 3
$ cd ..
# push from shallow to shallow
$ cd shallow
$ echo a > a
$ hg commit -qAm a
$ hg push ssh://user@dummy/$TESTTMP/shallow2
pushing to ssh://user@dummy/$TESTTMP/shallow2
searching for changes
remote: adding changesets
remote: adding manifests
remote: adding file changes
remote: added 1 changesets with 1 changes to 1 files
$ cd ../shallow2
$ hg up
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ cat a
a
# verify files are read-only
$ ls -l .hg/store/data
total * (glob)
drwxrwxr-x* 11f6ad8ec52a2984abaafd7c3b516503785c2072 (glob)
drwxrwxr-x* 395df8f7c51f007019cb30201c49e884b46b92fa (glob)
drwxrwxr-x* 86f7e437faa5a7fce15d1ddcb9eaeaea377667b8 (glob)
drwxrwxr-x* 95cb0bfd2977c761298d9624e4b4d4c72a39974a (glob)
$ ls -l .hg/store/data/395df8f7c51f007019cb30201c49e884b46b92fa
total * (glob)
-r--r--r--* 69a1b67522704ec122181c0890bd16e9d3e7516a (glob)
-r--r--r--* 69a1b67522704ec122181c0890bd16e9d3e7516a_old (glob)
$ cd ..
# push from shallow to full
$ cd shallow
$ hg push
pushing to ssh://user@dummy/master
searching for changes
remote: adding changesets
remote: adding manifests
remote: adding file changes
remote: added 2 changesets with 2 changes to 2 files
$ cd ../master
$ hg log -l 1 --style compact
3[tip] 1489bbbc46f0 1970-01-01 00:00 +0000 test
a
$ hg up
2 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ cat a
a
# push public commits
$ cd ../shallow
$ echo p > p
$ hg commit -qAm p
$ hg phase -f -p -r .
$ echo d > d
$ hg commit -qAm d
$ cd ../shallow2
$ hg pull ../shallow
pulling from ../shallow
searching for changes
adding changesets
adding manifests
adding file changes
added 2 changesets with 2 changes to 2 files
new changesets 3a2e32c04641:cedeb4167c1f (1 drafts)
2 local changesets published (?)
(run 'hg update' to get a working copy)
$ cd ..
# Test pushing from shallow to shallow with multiple manifests introducing the
# same filenode. Test this by constructing two separate histories of file 'c'
# that share a file node and verifying that the history works after pushing.
$ hg init multimf-master
$ hgcloneshallow ssh://user@dummy/multimf-master multimf-shallow -q
$ hgcloneshallow ssh://user@dummy/multimf-master multimf-shallow2 -q
$ cd multimf-shallow
$ echo a > a
$ hg commit -qAm a
$ echo b > b
$ hg commit -qAm b
$ echo c > c
$ hg commit -qAm c1
$ hg up -q 0
$ echo c > c
$ hg commit -qAm c2
$ echo cc > c
$ hg commit -qAm c22
$ hg log -G -T '{rev} {desc}\n'
@ 4 c22
|
o 3 c2
|
| o 2 c1
| |
| o 1 b
|/
o 0 a
$ cd ../multimf-shallow2
- initial commit to prevent hg pull from being a clone
$ echo z > z && hg commit -qAm z
$ hg pull -f ssh://user@dummy/$TESTTMP/multimf-shallow
pulling from ssh://user@dummy/$TESTTMP/multimf-shallow
searching for changes
warning: repository is unrelated
requesting all changes
adding changesets
adding manifests
adding file changes
added 5 changesets with 4 changes to 3 files (+2 heads)
new changesets cb9a9f314b8b:d8f06a4c6d38 (5 drafts)
(run 'hg heads' to see heads, 'hg merge' to merge)
$ hg up -q 5
$ hg log -f -T '{rev}\n' c
5
4