branchmap: pass changelog into branchmap functions
As part of building the branchmap, we loop over revs and call branchmap()
or _branchmap(). Previously, these functions were accessing repo.changelog.
We know from past experience that repo.changelog in loops is bad for
performance.
This commit teaches the branchmap code to pass a changelog instance into
branchmap() and _branchmap() so we don't need to pay this penalty.
On my MBP, this appears to show a speedup on a clone of the
mozilla-unified repo:
$ hg perfbranchmap --clear-revbranch
! base
! wall 21.078160 comb 21.070000 user 20.920000 sys 0.150000 (best of 3)
! wall 20.574682 comb 20.560000 user 20.400000 sys 0.160000 (best of 3)
$ hg perfbranchmap
! base
! wall 4.880413 comb 4.870000 user 4.860000 sys 0.010000 (best of 3)
! wall 4.573968 comb 4.560000 user 4.550000 sys 0.010000 (best of 3)
Differential Revision: https://phab.mercurial-scm.org/D5161
$ cat >> $HGRCPATH << EOF
> [extensions]
> fastannotate=
> [fastannotate]
> mainbranch=main
> EOF
$ hg init repo
$ cd repo
add or rename files on top of the master branch
$ echo a1 > a
$ echo b1 > b
$ hg commit -qAm 1
$ hg bookmark -i main
$ hg fastannotate --debug -nf b
fastannotate: b: 1 new changesets in the main branch
0 b: b1
$ hg fastannotate --debug -nf a
fastannotate: a: 1 new changesets in the main branch
0 a: a1
$ echo a2 >> a
$ cat > b << EOF
> b0
> b1
> EOF
$ hg mv a t
$ hg mv b a
$ hg mv t b
$ hg commit -m 'swap names'
existing linelogs are not helpful with such renames in side branches
$ hg fastannotate --debug -nf a
fastannotate: a: linelog cannot help in annotating this revision
1 a: b0
0 b: b1
$ hg fastannotate --debug -nf b
fastannotate: b: linelog cannot help in annotating this revision
0 a: a1
1 b: a2
move main branch forward, rebuild should happen
$ hg bookmark -i main -r . -q
$ hg fastannotate --debug -nf b
fastannotate: b: cache broken and deleted
fastannotate: b: 2 new changesets in the main branch
0 a: a1
1 b: a2
$ hg fastannotate --debug -nf b
fastannotate: b: using fast path (resolved fctx: True)
0 a: a1
1 b: a2
for rev 0, the existing linelog is still useful for a, but not for b
$ hg fastannotate --debug -nf a -r 0
fastannotate: a: using fast path (resolved fctx: True)
0 a: a1
$ hg fastannotate --debug -nf b -r 0
fastannotate: b: linelog cannot help in annotating this revision
0 b: b1
a rebuild can also be triggered if "the main branch last time" mismatches
$ echo a3 >> a
$ hg commit -m a3
$ cat >> b << EOF
> b3
> b4
> EOF
$ hg commit -m b4
$ hg bookmark -i main -q
$ hg fastannotate --debug -nf a
fastannotate: a: cache broken and deleted
fastannotate: a: 3 new changesets in the main branch
1 a: b0
0 b: b1
2 a: a3
$ hg fastannotate --debug -nf a
fastannotate: a: using fast path (resolved fctx: True)
1 a: b0
0 b: b1
2 a: a3
linelog can be updated without being helpful
$ hg mv a t
$ hg mv b a
$ hg mv t b
$ hg commit -m 'swap names again'
$ hg fastannotate --debug -nf b
fastannotate: b: 1 new changesets in the main branch
1 a: b0
0 b: b1
2 a: a3
$ hg fastannotate --debug -nf b
fastannotate: b: linelog cannot help in annotating this revision
1 a: b0
0 b: b1
2 a: a3
move main branch forward again, rebuilds are one-time
$ hg bookmark -i main -q
$ hg fastannotate --debug -nf a
fastannotate: a: cache broken and deleted
fastannotate: a: 4 new changesets in the main branch
0 a: a1
1 b: a2
3 b: b3
3 b: b4
$ hg fastannotate --debug -nf b
fastannotate: b: cache broken and deleted
fastannotate: b: 4 new changesets in the main branch
1 a: b0
0 b: b1
2 a: a3
$ hg fastannotate --debug -nf a
fastannotate: a: using fast path (resolved fctx: True)
0 a: a1
1 b: a2
3 b: b3
3 b: b4
$ hg fastannotate --debug -nf b
fastannotate: b: using fast path (resolved fctx: True)
1 a: b0
0 b: b1
2 a: a3
list changeset hashes to improve readability
$ hg log -T '{rev}:{node}\n'
4:980e1ab8c516350172928fba95b49ede3b643dca
3:14e123fedad9f491f5dde0beca2a767625a0a93a
2:96495c41e4c12218766f78cdf244e768d7718b0f
1:35c2b781234c994896aba36bd3245d3104e023df
0:653e95416ebb5dbcc25bbc7f75568c9e01f7bd2f
annotate a revision not in the linelog. linelog cannot be used, but does not get rebuilt either
$ hg fastannotate --debug -nf a -r 96495c41e4c12218766f78cdf244e768d7718b0f
fastannotate: a: linelog cannot help in annotating this revision
1 a: b0
0 b: b1
2 a: a3
$ hg fastannotate --debug -nf a -r 2
fastannotate: a: linelog cannot help in annotating this revision
1 a: b0
0 b: b1
2 a: a3
$ hg fastannotate --debug -nf a -r .
fastannotate: a: using fast path (resolved fctx: True)
0 a: a1
1 b: a2
3 b: b3
3 b: b4
annotate an ancient revision where the path matches. linelog can be used
$ hg fastannotate --debug -nf a -r 0
fastannotate: a: using fast path (resolved fctx: True)
0 a: a1
$ hg fastannotate --debug -nf a -r 653e95416ebb5dbcc25bbc7f75568c9e01f7bd2f
fastannotate: a: using fast path (resolved fctx: False)
0 a: a1