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
#require no-windows
$ . "$TESTDIR/remotefilelog-library.sh"
$ hg init master
$ cd master
$ cat >> .hg/hgrc <<EOF
> [remotefilelog]
> server=True
> EOF
$ echo x > x
$ echo y > y
$ echo z > z
$ hg commit -qAm xy
$ cd ..
$ hgcloneshallow ssh://user@dummy/master shallow -q
3 files fetched over 1 fetches - (3 misses, 0.00% hit ratio) over *s (glob)
$ cd shallow
# status
$ clearcache
$ echo xx > x
$ echo yy > y
$ touch a
$ hg status
M x
M y
? a
1 files fetched over 1 fetches - (1 misses, 0.00% hit ratio) over *s (glob)
$ hg add a
$ hg status
M x
M y
A a
# diff
$ hg debugrebuilddirstate # fixes dirstate non-determinism
$ hg add a
$ clearcache
$ hg diff
diff -r f3d0bb0d1e48 x
--- a/x* (glob)
+++ b/x* (glob)
@@ -1,1 +1,1 @@
-x
+xx
diff -r f3d0bb0d1e48 y
--- a/y* (glob)
+++ b/y* (glob)
@@ -1,1 +1,1 @@
-y
+yy
3 files fetched over 1 fetches - (3 misses, 0.00% hit ratio) over *s (glob)
# local commit
$ clearcache
$ echo a > a
$ echo xxx > x
$ echo yyy > y
$ hg commit -m a
? files fetched over 1 fetches - (? misses, 0.00% hit ratio) over *s (glob)
# local commit where the dirstate is clean -- ensure that we do just one fetch
# (update to a commit on the server first)
$ hg --config debug.dirstate.delaywrite=1 up 0
2 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ clearcache
$ hg debugdirstate
n 644 2 * x (glob)
n 644 2 * y (glob)
n 644 2 * z (glob)
$ echo xxxx > x
$ echo yyyy > y
# run status early to avoid a flaky second fetch during commit.
$ hg st
M x
M y
\d+ files fetched over \d+ fetches .* (re) (?)
$ hg commit -m x
created new head
2 files fetched over 1 fetches - (2 misses, 0.00% hit ratio) over *s (glob)
# restore state for future tests
$ hg -q strip .
$ hg -q up tip
# rebase
$ clearcache
$ cd ../master
$ echo w > w
$ hg commit -qAm w
$ cd ../shallow
$ hg pull
pulling from ssh://user@dummy/master
searching for changes
adding changesets
adding manifests
adding file changes
added 1 changesets with 0 changes to 0 files (+1 heads)
new changesets fed61014d323
(run 'hg heads' to see heads, 'hg merge' to merge)
# run status early to avoid a flaky second fetch during commit
$ hg status
\d+ files fetched over \d+ fetches .* (re) (?)
$ hg rebase -d tip
rebasing 1:9abfe7bca547 "a"
saved backup bundle to $TESTTMP/shallow/.hg/strip-backup/9abfe7bca547-8b11e5ff-rebase.hg (glob)
3 files fetched over 2 fetches - (3 misses, 0.00% hit ratio) over *s (glob)
# strip
$ clearcache
$ hg debugrebuilddirstate # fixes dirstate non-determinism
$ hg strip -r .
2 files updated, 0 files merged, 1 files removed, 0 files unresolved
saved backup bundle to $TESTTMP/shallow/.hg/strip-backup/19edf50f4de7-df3d0f74-backup.hg (glob)
3 files fetched over 2 fetches - (3 misses, 0.00% hit ratio) over *s (glob)
# unbundle
$ clearcache
$ ls -A
.hg
w
x
y
z
$ hg debugrebuilddirstate # fixes dirstate non-determinism
$ hg unbundle .hg/strip-backup/19edf50f4de7-df3d0f74-backup.hg
adding changesets
adding manifests
adding file changes
added 1 changesets with 3 changes to 3 files
new changesets 19edf50f4de7 (1 drafts)
(run 'hg update' to get a working copy)
2 files fetched over 1 fetches - (2 misses, 0.00% hit ratio) over *s (glob)
$ hg up
3 files updated, 0 files merged, 0 files removed, 0 files unresolved
1 files fetched over 1 fetches - (1 misses, 0.00% hit ratio) over *s (glob)
$ cat a
a
# revert
$ clearcache
$ hg revert -r .~2 y z
no changes needed to z
1 files fetched over 1 fetches - (1 misses, 0.00% hit ratio) over *s (glob)
$ hg checkout -C -r . -q
# explicit bundle should produce full bundle file
$ hg bundle -r 2 --base 1 ../local.bundle
1 changesets found
1 files fetched over 1 fetches - (1 misses, 0.00% hit ratio) over *s (glob)
$ cd ..
$ hgcloneshallow ssh://user@dummy/master shallow2 -q
2 files fetched over 1 fetches - (2 misses, 0.00% hit ratio) over *s (glob)
$ cd shallow2
$ hg unbundle ../local.bundle
adding changesets
adding manifests
adding file changes
added 1 changesets with 3 changes to 3 files
new changesets 19edf50f4de7 (1 drafts)
(run 'hg update' to get a working copy)
$ hg log -r 2 --stat
changeset: 2:19edf50f4de7
tag: tip
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: a
a | 1 +
x | 2 +-
y | 2 +-
3 files changed, 3 insertions(+), 2 deletions(-)
# Merge
$ echo merge >> w
$ hg commit -m w
created new head
$ hg merge 2
3 files updated, 0 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ hg commit -m merge
$ hg strip -q -r ".^"
# commit without producing new node
$ cd $TESTTMP
$ hgcloneshallow ssh://user@dummy/master shallow3 -q
$ cd shallow3
$ echo 1 > A
$ hg commit -m foo -A A
$ hg log -r . -T '{node}\n'
383ce605500277f879b7460a16ba620eb6930b7f
$ hg update -r '.^' -q
$ echo 1 > A
$ hg commit -m foo -A A
warning: commit already existed in the repository!
$ hg log -r . -T '{node}\n'
383ce605500277f879b7460a16ba620eb6930b7f