revset: stop serializing node when using "%ln"
Turning hundred of thousand of node from node to hex and back can be slow… what
about we stop doing it?
In many case were we are using node id we should be using revision id. However
this is not a good reason to have a stupidly slow implementation of "%ln".
This caught my attention again because the phase discovery during push make an
extensive use of "%ln" or huge set. In absolute, that phase discovery probably
should use "%ld" and need to improves its algorithmic complexity, but improving
"%ln" seems simple and long overdue. This greatly speeds up `hg push` on
repository with many drafts.
Here are some relevant poulpe benchmarks:
### data-env-vars.name = mozilla-try-2023-03-22-zstd-sparse-revlog
# benchmark.name = hg.command.push
# bin-env-vars.hg.flavor = default
# bin-env-vars.hg.py-re2-module = default
# benchmark.variants.explicit-rev = all-out-heads
# benchmark.variants.issue6528 = disabled
# benchmark.variants.protocol = ssh
# benchmark.variants.reuse-external-delta-parent = default
## benchmark.variants.revs = any-1-extra-rev
before: 44.235070
after: 20.416329 (-53.85%, -23.82)
## benchmark.variants.revs = any-100-extra-rev
before: 49.234697
after: 26.519829 (-46.14%, -22.71)
### benchmark.name = hg.command.bundle
# bin-env-vars.hg.flavor = default
# bin-env-vars.hg.py-re2-module = default
# benchmark.variants.revs = all
# benchmark.variants.type = none-streamv2
## data-env-vars.name = heptapod-public-2024-03-25-zstd-sparse-revlog
before: 10.138396
after: 7.750458 (-23.55%, -2.39)
## data-env-vars.name = mercurial-public-2024-03-22-zstd-sparse-revlog
before: 1.263859
after: 0.700229 (-44.60%, -0.56)
## data-env-vars.name = mozilla-try-2023-03-22-zstd-sparse-revlog
before: 399.484481
after: 346.5089 (-13.26%, -52.98)
## data-env-vars.name = pypy-2024-03-22-zstd-sparse-revlog
before: 4.540080
after: 3.401700 (-25.07%, -1.14)
## data-env-vars.name = tryton-public-2024-03-22-zstd-sparse-revlog
before: 2.975765
after: 1.870798 (-37.13%, -1.10)
$ 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