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
$ cat <<'EOF' >> "$HGRCPATH"
> [extensions]
> convert =
> [templates]
> l = '{rev}:{node|short} p={p1rev},{p2rev} m={manifest} f={files|json}'
> EOF
$ check_convert_identity () {
> hg convert -q "$1" "$1.converted"
> hg outgoing -q -R "$1.converted" "$1"
> if [ "$?" != 1 ]; then
> echo '*** BUG: hash changes on convert ***'
> hg log -R "$1.converted" -GTl
> fi
> }
Files added at both parents:
$ hg init added-both
$ cd added-both
$ touch a b c
$ hg ci -qAm0 a
$ hg ci -qAm1 b
$ hg up -q 0
$ hg ci -qAm2 c
$ hg merge
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ hg ci --debug -m merge
committing files:
b
not reusing manifest (no file change in changelog, but manifest differs)
committing manifest
committing changelog
updating the branch cache
committed changeset 3:7aa8a293f5d97377037afc21e871e036e718d659
$ hg log -GTl
@ 3:7aa8a293f5d9 p=2,1 m=3:8667461869a1 f=[]
|\
| o 2:e0ea47086fce p=0,-1 m=2:b2e5b07f9374 f=["c"]
| |
o | 1:64d01526d4c2 p=0,-1 m=1:686dbf0aeca4 f=["b"]
|/
o 0:487a0a245cea p=-1,-1 m=0:8515d4bfda76 f=["a"]
$ cd ..
$ check_convert_identity added-both
Files added at both parents, but the other removed at the merge:
(In this case, ctx.files() after the commit contains the removed file "b", but
its manifest does not differ from p1.)
$ hg init added-both-removed-at-merge
$ cd added-both-removed-at-merge
$ touch a b c
$ hg ci -qAm0 a
$ hg ci -qAm1 b
$ hg up -q 0
$ hg ci -qAm2 c
$ hg merge
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ hg rm -f b
$ hg ci --debug -m merge
committing files:
committing manifest
committing changelog
updating the branch cache
committed changeset 3:915745f3ca3d9d699925269474c2d0a9526e8dfa
$ hg log -GTl
@ 3:915745f3ca3d p=2,1 m=3:8e9cf3456921 f=["b"]
|\
| o 2:e0ea47086fce p=0,-1 m=2:b2e5b07f9374 f=["c"]
| |
o | 1:64d01526d4c2 p=0,-1 m=1:686dbf0aeca4 f=["b"]
|/
o 0:487a0a245cea p=-1,-1 m=0:8515d4bfda76 f=["a"]
$ cd ..
$ check_convert_identity added-both
An identical file added at both parents:
$ hg init added-identical
$ cd added-identical
$ touch a b
$ hg ci -qAm0 a
$ hg ci -qAm1 b
$ hg up -q 0
$ touch b
$ hg ci -qAm2 b
$ hg merge
0 files updated, 0 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ hg ci --debug -m merge
reusing manifest from p1 (no file change)
committing changelog
updating the branch cache
committed changeset 3:de26182cd210f0c3fb175ca7616704ab963d3024
$ hg log -GTl
@ 3:de26182cd210 p=2,1 m=1:686dbf0aeca4 f=[]
|\
| o 2:f00991f11eca p=0,-1 m=1:686dbf0aeca4 f=["b"]
| |
o | 1:64d01526d4c2 p=0,-1 m=1:686dbf0aeca4 f=["b"]
|/
o 0:487a0a245cea p=-1,-1 m=0:8515d4bfda76 f=["a"]
$ cd ..
$ check_convert_identity added-identical
#if execbit
An identical file added at both parents, but the flag differs. Take local:
$ hg init flag-change-take-p1
$ cd flag-change-take-p1
$ touch a b
$ hg ci -qAm0 a
$ hg ci -qAm1 b
$ hg up -q 0
$ touch b
$ chmod +x b
$ hg ci -qAm2 b
$ hg merge
warning: cannot merge flags for b without common ancestor - keeping local flags
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ chmod +x b
$ hg ci --debug -m merge
committing files:
b
reusing manifest from p1 (listed files actually unchanged)
committing changelog
updating the branch cache
committed changeset 3:c8d50407916ef8a5a97cb6e36ca9bc844a6ee13e
$ hg log -GTl
@ 3:c8d50407916e p=2,1 m=2:36b69ba4b24b f=[]
|\
| o 2:99451f16b3f5 p=0,-1 m=2:36b69ba4b24b f=["b"]
| |
o | 1:64d01526d4c2 p=0,-1 m=1:686dbf0aeca4 f=["b"]
|/
o 0:487a0a245cea p=-1,-1 m=0:8515d4bfda76 f=["a"]
$ hg files -vr3
0 a
0 x b
$ cd ..
$ check_convert_identity flag-change-take-p1
An identical file added at both parents, but the flag differs. Take other:
$ hg init flag-change-take-p2
$ cd flag-change-take-p2
$ touch a b
$ hg ci -qAm0 a
$ hg ci -qAm1 b
$ hg up -q 0
$ touch b
$ chmod +x b
$ hg ci -qAm2 b
$ hg merge
warning: cannot merge flags for b without common ancestor - keeping local flags
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ chmod -x b
$ hg ci --debug -m merge
committing files:
b
committing manifest
committing changelog
updating the branch cache
committed changeset 3:06a62a687d87c7d8944743dee1ee9d8c66b3f6e3
$ hg log -GTl
@ 3:06a62a687d87 p=2,1 m=3:2a315ba1aa45 f=["b"]
|\
| o 2:99451f16b3f5 p=0,-1 m=2:36b69ba4b24b f=["b"]
| |
o | 1:64d01526d4c2 p=0,-1 m=1:686dbf0aeca4 f=["b"]
|/
o 0:487a0a245cea p=-1,-1 m=0:8515d4bfda76 f=["a"]
$ hg files -vr3
0 a
0 b
$ cd ..
$ check_convert_identity flag-change-take-p2
#endif
An identical file added at both parents, one more file added at p2:
$ hg init added-some-p2
$ cd added-some-p2
$ touch a b c
$ hg ci -qAm0 a
$ hg ci -qAm1 b
$ hg ci -qAm2 c
$ hg up -q 0
$ touch b
$ hg ci -qAm3 b
$ hg merge
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ hg ci --debug -m merge
committing files:
c
not reusing manifest (no file change in changelog, but manifest differs)
committing manifest
committing changelog
updating the branch cache
committed changeset 4:f7fbc4e4d9a8fde03ba475adad675578c8bf472d
$ hg log -GTl
@ 4:f7fbc4e4d9a8 p=3,2 m=3:92acd5bfd716 f=[]
|\
| o 3:e9d9f3cc981f p=0,-1 m=1:686dbf0aeca4 f=["b"]
| |
o | 2:93c5529a4ec7 p=1,-1 m=2:ae25a31b30b3 f=["c"]
| |
o | 1:64d01526d4c2 p=0,-1 m=1:686dbf0aeca4 f=["b"]
|/
o 0:487a0a245cea p=-1,-1 m=0:8515d4bfda76 f=["a"]
$ cd ..
$ check_convert_identity added-some-p2
An identical file added at both parents, one more file added at p1:
(In this case, p1 manifest is reused at the merge commit, which means the
manifest DAG does not have the same shape as the changelog.)
$ hg init added-some-p1
$ cd added-some-p1
$ touch a b
$ hg ci -qAm0 a
$ hg ci -qAm1 b
$ hg up -q 0
$ touch b c
$ hg ci -qAm2 b
$ hg ci -qAm3 c
$ hg merge
0 files updated, 0 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ hg ci --debug -m merge
reusing manifest from p1 (no file change)
committing changelog
updating the branch cache
committed changeset 4:a9f0f589a913f5a149dc10dfbd5af726977c36c4
$ hg log -GTl
@ 4:a9f0f589a913 p=3,1 m=2:ae25a31b30b3 f=[]
|\
| o 3:b8dc385241b5 p=2,-1 m=2:ae25a31b30b3 f=["c"]
| |
| o 2:f00991f11eca p=0,-1 m=1:686dbf0aeca4 f=["b"]
| |
o | 1:64d01526d4c2 p=0,-1 m=1:686dbf0aeca4 f=["b"]
|/
o 0:487a0a245cea p=-1,-1 m=0:8515d4bfda76 f=["a"]
$ cd ..
$ check_convert_identity added-some-p1
A file added at p2, a named branch created at p1:
$ hg init named-branch-p1
$ cd named-branch-p1
$ touch a b
$ hg ci -qAm0 a
$ hg ci -qAm1 b
$ hg up -q 0
$ hg branch -q foo
$ hg ci -m2
$ hg merge default
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ hg ci --debug -m merge
committing files:
b
not reusing manifest (no file change in changelog, but manifest differs)
committing manifest
committing changelog
updating the branch cache
committed changeset 3:fb97d83b02fd072295cfc2171f21b7d38509bfd7
$ hg log -GT'{l} branch={branch}'
@ 3:fb97d83b02fd p=2,1 m=2:9091c64f4ea1 f=[] branch=foo
|\
| o 2:a3a9fa6587e5 p=0,-1 m=0:8515d4bfda76 f=[] branch=foo
| |
o | 1:64d01526d4c2 p=0,-1 m=1:686dbf0aeca4 f=["b"] branch=default
|/
o 0:487a0a245cea p=-1,-1 m=0:8515d4bfda76 f=["a"] branch=default
$ cd ..
$ check_convert_identity named-branch-p1
A file added at p1, a named branch created at p2:
(In this case, p1 manifest is reused at the merge commit, which means the
manifest DAG does not have the same shape as the changelog.)
$ hg init named-branch-p2
$ cd named-branch-p2
$ touch a b
$ hg ci -qAm0 a
$ hg branch -q foo
$ hg ci -m1
$ hg up -q 0
$ hg ci -qAm1 b
$ hg merge foo
0 files updated, 0 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ hg ci --debug -m merge
reusing manifest from p1 (no file change)
committing changelog
updating the branch cache
committed changeset 3:036823e24692218324d4af43b07ff89f8a000096
$ hg log -GT'{l} branch={branch}'
@ 3:036823e24692 p=2,1 m=1:686dbf0aeca4 f=[] branch=default
|\
| o 2:64d01526d4c2 p=0,-1 m=1:686dbf0aeca4 f=["b"] branch=default
| |
o | 1:da38c8e00727 p=0,-1 m=0:8515d4bfda76 f=[] branch=foo
|/
o 0:487a0a245cea p=-1,-1 m=0:8515d4bfda76 f=["a"] branch=default
$ cd ..
$ check_convert_identity named-branch-p2
A file changed once at both parents, but amended to have identical content:
$ hg init amend-p1
$ cd amend-p1
$ touch a
$ hg ci -qAm0 a
$ echo foo > a
$ hg ci -m1
$ hg up -q 0
$ echo bar > a
$ hg ci -qm2
$ echo foo > a
$ hg ci -qm3 --amend
$ hg merge
0 files updated, 0 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ hg ci --debug -m merge
reusing manifest from p1 (no file change)
committing changelog
updating the branch cache
committed changeset 3:314e5bc5adf5c58ea571efabe33eedba20a201aa
$ hg log -GT'{l} branch={branch}'
@ 3:314e5bc5adf5 p=2,1 m=1:d33ea248bd73 f=[] branch=default
|\
| o 2:de9c64f226a3 p=0,-1 m=1:d33ea248bd73 f=["a"] branch=default
| |
o | 1:6a74aec01b3c p=0,-1 m=1:d33ea248bd73 f=["a"] branch=default
|/
o 0:487a0a245cea p=-1,-1 m=0:8515d4bfda76 f=["a"] branch=default
$ cd ..
$ check_convert_identity amend-p1