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
Test for the full copytracing algorithm
=======================================
Initial Setup
=============
use git diff to see rename
$ cat << EOF >> $HGRCPATH
> [diff]
> git=yes
> EOF
Setup an history where one side copy and rename a file (and update it) while the other side update it.
$ hg init t
$ cd t
$ echo 1 > a
$ hg ci -qAm "first"
$ hg cp a b
$ hg mv a c
$ echo 2 >> b
$ echo 2 >> c
$ hg ci -qAm "second"
$ hg co -C 0
1 files updated, 0 files merged, 2 files removed, 0 files unresolved
$ echo 0 > a
$ echo 1 >> a
$ hg ci -qAm "other"
$ hg log -G --patch
@ changeset: 2:add3f11052fa
| tag: tip
| parent: 0:b8bf91eeebbc
| user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: other
|
| diff --git a/a b/a
| --- a/a
| +++ b/a
| @@ -1,1 +1,2 @@
| +0
| 1
|
| o changeset: 1:17c05bb7fcb6
|/ user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: second
|
| diff --git a/a b/b
| rename from a
| rename to b
| --- a/a
| +++ b/b
| @@ -1,1 +1,2 @@
| 1
| +2
| diff --git a/a b/c
| copy from a
| copy to c
| --- a/a
| +++ b/c
| @@ -1,1 +1,2 @@
| 1
| +2
|
o changeset: 0:b8bf91eeebbc
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: first
diff --git a/a b/a
new file mode 100644
--- /dev/null
+++ b/a
@@ -0,0 +1,1 @@
+1
Test Simple Merge
=================
$ hg merge --debug
unmatched files in other:
b
c
all copies found (* = to merge, ! = divergent, % = renamed and deleted):
on remote side:
src: 'a' -> dst: 'b' *
src: 'a' -> dst: 'c' *
checking for directory renames
resolving manifests
branchmerge: True, force: False, partial: False
ancestor: b8bf91eeebbc, local: add3f11052fa+, remote: 17c05bb7fcb6
starting 4 threads for background file closing (?)
preserving a for resolve of b
preserving a for resolve of c
removing a
b: remote moved from a -> m
picked tool ':merge' for b (binary False symlink False changedelete False)
merging a and b to b
my b@add3f11052fa+ other b@17c05bb7fcb6 ancestor a@b8bf91eeebbc
premerge successful
c: remote moved from a -> m
picked tool ':merge' for c (binary False symlink False changedelete False)
merging a and c to c
my c@add3f11052fa+ other c@17c05bb7fcb6 ancestor a@b8bf91eeebbc
premerge successful
0 files updated, 2 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
file b
$ cat b
0
1
2
file c
$ cat c
0
1
2
Test disabling copy tracing
===========================
first verify copy metadata was kept
-----------------------------------
$ hg up -qC 2
$ hg rebase --keep -d 1 -b 2 --config extensions.rebase=
rebasing 2:add3f11052fa tip "other"
merging b and a to b
merging c and a to c
$ cat b
0
1
2
next verify copy metadata is lost when disabled
------------------------------------------------
$ hg strip -r . --config extensions.strip=
2 files updated, 0 files merged, 0 files removed, 0 files unresolved
saved backup bundle to $TESTTMP/t/.hg/strip-backup/550bd84c0cd3-fc575957-backup.hg
$ hg up -qC 2
$ hg rebase --keep -d 1 -b 2 --config extensions.rebase= --config experimental.copytrace=off --config ui.interactive=True << EOF
> c
> EOF
rebasing 2:add3f11052fa tip "other"
file 'a' was deleted in local [dest] but was modified in other [source].
You can use (c)hanged version, leave (d)eleted, or leave (u)nresolved.
What do you want to do? c
$ cat b
1
2
$ cd ..
Verify disabling copy tracing still keeps copies from rebase source
-------------------------------------------------------------------
$ hg init copydisable
$ cd copydisable
$ touch a
$ hg ci -Aqm 'add a'
$ touch b
$ hg ci -Aqm 'add b, c'
$ hg cp b x
$ echo x >> x
$ hg ci -qm 'copy b->x'
$ hg up -q 1
$ touch z
$ hg ci -Aqm 'add z'
$ hg log -G -T '{rev} {desc}\n'
@ 3 add z
|
| o 2 copy b->x
|/
o 1 add b, c
|
o 0 add a
$ hg rebase -d . -b 2 --config extensions.rebase= --config experimental.copytrace=off
rebasing 2:6adcf8c12e7d "copy b->x"
saved backup bundle to $TESTTMP/copydisable/.hg/strip-backup/6adcf8c12e7d-ce4b3e75-rebase.hg
$ hg up -q 3
$ hg log -f x -T '{rev} {desc}\n'
3 copy b->x
1 add b, c
$ cd ../
test storage preservation
-------------------------
Verify rebase do not discard recorded copies data when copy tracing usage is
disabled.
Setup
$ hg init copydisable3
$ cd copydisable3
$ touch a
$ hg ci -Aqm 'add a'
$ hg cp a b
$ hg ci -Aqm 'copy a->b'
$ hg mv b c
$ hg ci -Aqm 'move b->c'
$ hg up -q 0
$ hg cp a b
$ echo b >> b
$ hg ci -Aqm 'copy a->b (2)'
$ hg log -G -T '{rev} {desc}\n'
@ 3 copy a->b (2)
|
| o 2 move b->c
| |
| o 1 copy a->b
|/
o 0 add a
Actual Test
A file is copied on one side and has been moved twice on the other side. the
file is copied from `0:a`, so the file history of the `3:b` should trace directly to `0:a`.
$ hg rebase -d 2 -s 3 --config extensions.rebase= --config experimental.copytrace=off
rebasing 3:47e1a9e6273b tip "copy a->b (2)"
saved backup bundle to $TESTTMP/copydisable3/.hg/strip-backup/47e1a9e6273b-2d099c59-rebase.hg
$ hg log -G -f b
@ changeset: 3:76024fb4b05b
: tag: tip
: user: test
: date: Thu Jan 01 00:00:00 1970 +0000
: summary: copy a->b (2)
:
o changeset: 0:ac82d8b1f7c4
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: add a