perf: clear vfs audit_cache before each run
When generating a stream clone, we spend a large amount of time auditing path.
Before this changes, the first run was warming the vfs cache for the other
runs, leading to a large runtime difference and a "faulty" reported timing for
the operation.
We now clear this important cache between run to get a more realistic timing.
Below are some example of median time change when clearing these cases. The
maximum time for a run did not changed significantly.
### data-env-vars.name = mozilla-central-2018-08-01-zstd-sparse-revlog
# benchmark.name = hg.perf.exchange.stream.generate
# bin-env-vars.hg.flavor = default
# bin-env-vars.hg.py-re2-module = default
# benchmark.variants.version = latest
no-clearing: 17.289905
cache-clearing: 21.587965 (+24.86%, +4.30)
## data-env-vars.name = mozilla-central-2024-03-22-zstd-sparse-revlog
no-clearing: 32.670748
cache-clearing: 40.467095 (+23.86%, +7.80)
## data-env-vars.name = mozilla-try-2019-02-18-zstd-sparse-revlog
no-clearing: 37.838858
cache-clearing: 46.072749 (+21.76%, +8.23)
## data-env-vars.name = mozilla-unified-2024-03-22-zstd-sparse-revlog
no-clearing: 32.969395
cache-clearing: 39.646209 (+20.25%, +6.68)
In addition, this significantly reduce the timing difference between the
performance command, from the perf extensions and a `real `hg bundle` call
producing a stream bundle. Some significant differences remain especially on
the "mozilla-try" repositories, but they are now smaller.
Note that some of that difference will actually not be
attributable to the stream generation (like maybe phases or branch map
computation).
Below are some benchmarks done on a currently draft changeset fixing some
unrelated slowness in `hg bundle` (34a78972af409d1ff37c29e60f6ca811ad1a457d)
### data-env-vars.name = mozilla-central-2018-08-01-zstd-sparse-revlog
# bin-env-vars.hg.flavor = default
# bin-env-vars.hg.py-re2-module = default
hg.perf.exchange.stream.generate: 21.587965
hg.command.bundle: 24.301799 (+12.57%, +2.71)
## data-env-vars.name = mozilla-central-2024-03-22-zstd-sparse-revlog
hg.perf.exchange.stream.generate: 40.467095
hg.command.bundle: 44.831317 (+10.78%, +4.36)
## data-env-vars.name = mozilla-unified-2024-03-22-zstd-sparse-revlog
hg.perf.exchange.stream.generate: 39.646209
hg.command.bundle: 45.395258 (+14.50%, +5.75)
## data-env-vars.name = mozilla-try-2019-02-18-zstd-sparse-revlog
hg.perf.exchange.stream.generate: 46.072749
hg.command.bundle: 55.882608 (+21.29%, +9.81)
## data-env-vars.name = mozilla-try-2023-03-22-zlib-general-delta
hg.perf.exchange.stream.generate: 334.716708
hg.command.bundle: 377.856767 (+12.89%, +43.14)
## data-env-vars.name = mozilla-try-2023-03-22-zstd-sparse-revlog
hg.perf.exchange.stream.generate: 302.972301
hg.command.bundle: 326.098755 (+7.63%, +23.13)
$ hg init t
$ cd t
$ echo 1 > foo
$ hg ci -Am1 # 0
adding foo
$ hg branch branchA
marked working directory as branch branchA
(branches are permanent and global, did you want a bookmark?)
$ echo a1 > foo
$ hg ci -ma1 # 1
$ cd ..
$ hg init tt
$ cd tt
$ hg pull ../t
pulling from ../t
requesting all changes
adding changesets
adding manifests
adding file changes
added 2 changesets with 2 changes to 1 files
new changesets 495a0ec48aaf:50e089d141b7
(run 'hg update' to get a working copy)
$ hg up branchA
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ cd ../t
$ echo a2 > foo
$ hg ci -ma2 # 2
Create branch B:
$ hg up 0
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg branch branchB
marked working directory as branch branchB
$ echo b1 > foo
$ hg ci -mb1 # 3
$ cd ../tt
A new branch is there
$ hg pull -u ../t
pulling from ../t
searching for changes
adding changesets
adding manifests
adding file changes
added 2 changesets with 2 changes to 1 files (+1 heads)
new changesets 9f878dea0b96:5be59ce5067b
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
Develop both branches:
$ cd ../t
$ hg up branchA
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ echo a3 > foo
$ hg ci -ma3 # 4
$ hg up branchB
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ echo b2 > foo
$ hg ci -mb2 # 5
$ cd ../tt
Should succeed, no new heads:
$ hg pull -u ../t
pulling from ../t
searching for changes
adding changesets
adding manifests
adding file changes
added 2 changesets with 2 changes to 1 files
new changesets 7c8fe7e20c32:453e93fa00a5
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
Add a head on other branch:
$ cd ../t
$ hg up branchA
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ echo a4 > foo
$ hg ci -ma4 # 6
$ hg up branchB
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ echo b3.1 > foo
$ hg ci -m b3.1 # 7
$ hg up 5
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ echo b3.2 > foo
$ hg ci -m b3.2 # 8
created new head
$ cd ../tt
Should succeed because there is only one head on our branch:
$ hg pull -u ../t
pulling from ../t
searching for changes
adding changesets
adding manifests
adding file changes
added 3 changesets with 3 changes to 1 files (+1 heads)
new changesets da3a8a0161c6:b61cab8fe4e8
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ cd ../t
$ hg up -C branchA
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ echo a5.1 > foo
$ hg ci -ma5.1 # 9
$ hg up 6
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ echo a5.2 > foo
$ hg ci -ma5.2 # 10
created new head
$ hg up 7
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ echo b4.1 > foo
$ hg ci -m b4.1 # 11
$ hg up -C 8
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ echo b4.2 > foo
$ hg ci -m b4.2 # 12
$ cd ../tt
$ hg pull -u ../t
pulling from ../t
searching for changes
adding changesets
adding manifests
adding file changes
added 4 changesets with 4 changes to 1 files (+1 heads)
new changesets 0c4d148ae29e:ecfc3f4a6fd9
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
updated to "d740e1a584e7: a5.2"
1 other heads for branch "branchA"
Make changes on new branch on tt
$ hg up 6
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg branch branchC
marked working directory as branch branchC
$ echo b1 > bar
$ hg ci -Am "commit on branchC on tt"
adding bar
Make changes on default branch on t
$ cd ../t
$ hg up -C default
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ echo a1 > bar
$ hg ci -Am "commit on default on t"
adding bar
Pull branchC from tt
$ hg pull ../tt
pulling from ../tt
searching for changes
adding changesets
adding manifests
adding file changes
added 1 changesets with 1 changes to 1 files (+1 heads)
new changesets 7d8ffa4c0b22
13 local changesets published
(run 'hg heads' to see heads)
Make changes on default and branchC on tt
$ cd ../tt
$ hg pull ../t
pulling from ../t
searching for changes
adding changesets
adding manifests
adding file changes
added 1 changesets with 1 changes to 1 files (+1 heads)
new changesets 2b94b54b6b5f
1 local changesets published
(run 'hg heads' to see heads)
$ hg up -C default
2 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ echo a1 > bar1
$ hg ci -Am "commit on default on tt"
adding bar1
$ hg up branchC
2 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ echo a1 > bar2
$ hg ci -Am "commit on branchC on tt"
adding bar2
Make changes on default and branchC on t
$ cd ../t
$ hg up default
0 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ echo a1 > bar3
$ hg ci -Am "commit on default on t"
adding bar3
$ hg up branchC
2 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ echo a1 > bar4
$ hg ci -Am "commit on branchC on tt"
adding bar4
Pull from tt
$ hg pull ../tt
pulling from ../tt
searching for changes
adding changesets
adding manifests
adding file changes
added 2 changesets with 2 changes to 2 files (+2 heads)
new changesets eed40c14b407:e634733b0309
1 local changesets published
(run 'hg heads .' to see heads, 'hg merge' to merge)
$ cd ..