phases: rework the logic of _pushdiscoveryphase to bound complexity
This rework the various graph traversal in _pushdiscoveryphase to keep the
complexity in check.
This is done though a couple of things:
- first, limiting the space we have to explore, for example, if we are not in
publishing push, we don't need to consider remote draft roots that are also
draft locally, as there is nothing to be moved there.
- avoid unbounded descendant computation, and use the faster "rev between"
computation.
This provide a massive boost to performance when exchanging with repository with
a massive amount of draft, like mozilla-try:
### 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: 20.346590 seconds
after: 11.232059 seconds (-38.15%, -7.48 seconds)
## benchmark.variants.revs = any-100-extra-rev
before: 24.752051 seconds
after: 15.367412 seconds (-37.91%, -9.38 seconds)
After this changes, the push operation is still quite too slow. Some of this
can be attributed to general phases slowness (reading all the roots from disk
for example) and other know slowness (not using persistent-nodemap, branchmap,
tags, etc. We are also working on them, but with this series, phase discovery
during push no longer showing up in profile and this is a pretty nice and bit
low-hanging fruit out of the way.
### (same case as the above)
# benchmark.variants.revs = any-1-extra-rev
pre-%ln-change: 44.235070
this-changeset: 11.232059 seconds (-74.61%, -33.00 seconds)
# benchmark.variants.revs = any-100-extra-rev
pre-%ln-change: 49.234697
this-changeset: 15.367412 seconds (-68.79%, -33.87 seconds)
Note that with this change, the `hg push` performance is now much closer to the
`hg pull` performance, even it still lagging behind a bit. (and the overall
performance are still too slow).
### data-env-vars.name = mozilla-try-2023-03-22-ds2-pnm
# benchmark.variants.explicit-rev = all-out-heads
# benchmark.variants.issue6528 = disabled
# benchmark.variants.protocol = ssh
# benchmark.variants.pulled-delta-reuse-policy = default
# bin-env-vars.hg.flavor = rust
## benchmark.variants.revs = any-1-extra-rev
hg.command.pull: 6.517450
hg.command.push: 11.219888
## benchmark.variants.revs = any-100-extra-rev
hg.command.pull: 10.160991
hg.command.push: 14.251107
### data-env-vars.name = mozilla-try-2023-03-22-zstd-sparse-revlog
# 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.pulled-delta-reuse-policy = default
## bin-env-vars.hg.flavor = default
## benchmark.variants.revs = any-1-extra-rev
hg.command.pull: 8.577772
hg.command.push: 11.232059
## bin-env-vars.hg.flavor = default
## benchmark.variants.revs = any-100-extra-rev
hg.command.pull: 13.152976
hg.command.push: 15.367412
## bin-env-vars.hg.flavor = rust
## benchmark.variants.revs = any-1-extra-rev
hg.command.pull: 8.731982
hg.command.push: 11.178751
## bin-env-vars.hg.flavor = rust
## benchmark.variants.revs = any-100-extra-rev
hg.command.pull: 13.184236
hg.command.push: 15.620843
#testcases continuecommand continueflag
This emulates the effects of an hg pull --rebase in which the remote repo
already has one local mq patch
$ cat >> $HGRCPATH <<EOF
> [extensions]
> rebase=
> mq=
>
> [phases]
> publish=False
>
> [alias]
> tglog = log -G --template "{rev}: {node|short} '{desc}' tags: {tags}\n"
> EOF
#if continueflag
$ cat >> $HGRCPATH <<EOF
> [alias]
> continue = rebase --continue
> EOF
#endif
$ hg init a
$ cd a
$ hg qinit -c
$ echo c1 > c1
$ hg add c1
$ hg ci -m C1
$ echo r1 > r1
$ hg add r1
$ hg ci -m R1
$ hg up -q 0
$ hg qnew p0.patch -d '1 0'
$ echo p0 > p0
$ hg add p0
$ hg qref -m P0
$ hg qnew p1.patch -d '2 0'
$ echo p1 > p1
$ hg add p1
$ hg qref -m P1
$ hg export qtip > p1.patch
$ hg up -q -C 1
$ hg import p1.patch
applying p1.patch
$ rm p1.patch
$ hg up -q -C qtip
$ hg rebase -v
rebasing 2:13a46ce44f60 p0.patch qbase "P0"
resolving manifests
removing p0
getting r1
resolving manifests
getting p0
committing files:
p0
committing manifest
committing changelog
rebasing 3:148775c71080 p1.patch qtip "P1"
resolving manifests
note: not rebasing 3:148775c71080 p1.patch qtip "P1", its destination already has all its changes
rebase merging completed
updating mq patch p0.patch to 5:9ecc820b1737
$TESTTMP/a/.hg/patches/p0.patch
2 changesets found
uncompressed size of bundle content:
352 (changelog)
328 (manifests)
131 p0
131 p1
saved backup bundle to $TESTTMP/a/.hg/strip-backup/13a46ce44f60-5da6ecfb-rebase.hg
2 changesets found
uncompressed size of bundle content:
407 (changelog)
328 (manifests)
131 p0
131 p1
adding branch
adding changesets
adding manifests
adding file changes
added 2 changesets with 2 changes to 2 files
rebase completed
1 revisions have been skipped
$ hg tglog
@ 3: 9ecc820b1737 'P0' tags: p0.patch qbase qtip tip
|
o 2: 869d8b134a27 'P1' tags: qparent
|
o 1: da108f2755df 'R1' tags:
|
o 0: cd320d50b341 'C1' tags:
$ cd ..
$ hg init b
$ cd b
$ hg qinit -c
$ for i in r0 r1 r2 r3 r4 r5 r6;
> do
> echo $i > $i
> hg ci -Am $i
> done
adding r0
adding r1
adding r2
adding r3
adding r4
adding r5
adding r6
$ hg qimport -r 1:tip
$ hg up -q 0
$ for i in r1 r3 r7 r8;
> do
> echo $i > $i
> hg ci -Am branch2-$i
> done
adding r1
created new head
adding r3
adding r7
adding r8
$ echo somethingelse > r4
$ hg ci -Am branch2-r4
adding r4
$ echo r6 > r6
$ hg ci -Am branch2-r6
adding r6
$ hg up -q qtip
$ HGMERGE=internal:fail hg rebase
rebasing 1:b4bffa6e4776 qbase r1 "r1"
note: not rebasing 1:b4bffa6e4776 qbase r1 "r1", its destination already has all its changes
rebasing 2:c0fd129beb01 r2 "r2"
rebasing 3:6ff5b8feed8e r3 "r3"
note: not rebasing 3:6ff5b8feed8e r3 "r3", its destination already has all its changes
rebasing 4:094320fec554 r4 "r4"
unresolved conflicts (see 'hg resolve', then 'hg rebase --continue')
[240]
$ HGMERGE=internal:local hg resolve --all
(no more unresolved files)
continue: hg rebase --continue
$ hg continue
already rebased 1:b4bffa6e4776 qbase r1 "r1" as 057f55ff8f44
already rebased 2:c0fd129beb01 r2 "r2" as 1660ab13ce9a
already rebased 3:6ff5b8feed8e r3 "r3" as 1660ab13ce9a
rebasing 4:094320fec554 r4 "r4"
note: not rebasing 4:094320fec554 r4 "r4", its destination already has all its changes
rebasing 5:681a378595ba r5 "r5"
rebasing 6:512a1f24768b qtip r6 "r6"
note: not rebasing 6:512a1f24768b qtip r6 "r6", its destination already has all its changes
saved backup bundle to $TESTTMP/b/.hg/strip-backup/b4bffa6e4776-b9bfb84d-rebase.hg
$ hg tglog
@ 8: 0b9735ce8f0a 'r5' tags: qtip r5 tip
|
o 7: 1660ab13ce9a 'r2' tags: qbase r2
|
o 6: 057f55ff8f44 'branch2-r6' tags: qparent
|
o 5: 1d7287f8deb1 'branch2-r4' tags:
|
o 4: 3c10b9db2bd5 'branch2-r8' tags:
|
o 3: b684023158dc 'branch2-r7' tags:
|
o 2: d817754b1251 'branch2-r3' tags:
|
o 1: 0621a206f8a4 'branch2-r1' tags:
|
o 0: 222799e2f90b 'r0' tags:
$ cd ..