pierre-yves.david@ens-lyon.org [Mon, 19 Jun 2023 23:27:18 +0200] rev 50684
infinitepush: aggressively deprecated infinite push
We add a large warning and an explicit abort. Both can be disable through
config, but neither are explicitly documented. If any user exists I really want
them to get in touch with the community.
Raphaël Gomès <rgomes@octobus.net> [Tue, 13 Jun 2023 14:35:36 +0200] rev 50683
rust-dependencies: switch from `users` to `whoami`
`users` is unmaintained, with the maintainer apparently MIA. `whoami` is a
popular crate that does simple wrapping of platform-specific calls.
This makes the overhead from using `blackbox` lower. It used to be up 10ms
on slower hardware for both calls, now down to <1ms which is always good.
Raphaël Gomès <rgomes@octobus.net> [Mon, 12 Jun 2023 23:41:28 +0200] rev 50682
rust-hg-core: move from `ouroboros` to `self_cell`
`ouroboros` has a fundamental soundness problem that, while not applicable
today, could become applicable given new compiler optimizations.ยน
`self_cell` is a crate that accomplishes a lot of the same things that
`ouroboros` did while remaining sound (that is, unless a new soundness issue
is discovered) by not assuming as much about the memory layout of the program.
`self_cell` has been scrutinized heavily in the past few months by very
competent people, some from the compiler team and has shown no weaknesses
for a while, with a 1.0 stable release coming out a couple months ago.
Our internal API is exactly the same, this is just an implementation detail.
To reiterate, no actual soundness issue was found with our use of `ouroboros`,
but there might be evolutions of `rustc` (or even a future separate compiler)
that could generate unsound code.
[1] https://github.com/joshua-maros/ouroboros/issues/88
Pierre-Yves David <pierre-yves.david@octobus.net> [Fri, 02 Jun 2023 15:12:05 +0200] rev 50681
debug-revlog-stats: make it use the new store entry API
This give use free tree manifest support in the process.
Pierre-Yves David <pierre-yves.david@octobus.net> [Fri, 02 Jun 2023 15:10:50 +0200] rev 50680
store: use the revlog type from revlog's constant instead of custom one
We already have a revlog type that everybody use. So we use that one instead.
Pierre-Yves David <pierre-yves.david@octobus.net> [Mon, 12 Jun 2023 23:24:41 +0200] rev 50679
repair: use `is_manifestlog` to recognise manifest revlog
This is simpler that comparing flag, and we want to remove these flags anyway.
Pierre-Yves David <pierre-yves.david@octobus.net> [Tue, 06 Jun 2023 04:56:54 +0200] rev 50678
perf: add a perf::stream-consume
We know how long it take to generate, lets check how long it take to apply now.
Pierre-Yves David <pierre-yves.david@octobus.net> [Tue, 06 Jun 2023 04:09:05 +0200] rev 50677
perf: add a perf::stream-generate command
This record the time we take to generate a bundle.
Pierre-Yves David <pierre-yves.david@octobus.net> [Mon, 12 Jun 2023 18:04:09 +0200] rev 50676
perf: add a new "context" argument to timer
This allow to simple setup/teardown outside of the timed section. Especially
using object that need context manager, like a temporary files.
Pierre-Yves David <pierre-yves.david@octobus.net> [Tue, 06 Jun 2023 01:48:10 +0200] rev 50675
perf: add support for stream-v3 during benchmark
This is getting important as the v3 protocol will diverge from the v2 protocol.
Pierre-Yves David <pierre-yves.david@octobus.net> [Tue, 06 Jun 2023 01:43:48 +0200] rev 50674
perf: add a function to find a stream version generator
The logic is clearer and can be reused for other commands in the future.
Arseniy Alekseyev <aalekseyev@janestreet.com> [Thu, 18 May 2023 19:23:59 +0100] rev 50673
treemanifest: make `updatecaches` update the nodemaps for all directories
Without this, if the cache for a nested directory is in a bad state,
it's very hard to repair it.
Arseniy Alekseyev <aalekseyev@janestreet.com> [Wed, 31 May 2023 10:37:55 +0100] rev 50672
stream-clone: avoid opening a revlog in case we do not need it
Opening an revlog has a cost, especially if it is inline as we have to scan the
file and construct an index.
To prevent the associated slowdown, we just do a minimal scan to check that an
inline file is still inline, and simply stream the file without creating a
revlog when we can.
This provides a big boost compared to the previous changeset, even if the full
generation is still penalized by the initial gathering of information.
All benchmarks are run on linux with Python 3.10.7.
# benchmark.name = hg.exchange.stream.generate
# benchmark.variants.version = v2
### Compared to the previous changesets
We get a large win all across the board!
# mercurial-2018-08-01-zstd-sparse-revlog
before: 0.250694 seconds
after: 0.105986 seconds (-57.72%)
# pypy-2018-08-01-zstd-sparse-revlog
before: 3.885657 seconds
after: 1.709748 seconds (-56.00%)
# netbeans-2018-08-01-zstd-sparse-revlog
before: 16.679371 seconds
after: 7.687469 seconds (-53.91%)
# mozilla-central-2018-08-01-zstd-sparse-revlog
before: 38.575482 seconds
after: 17.520316 seconds (-54.58%)
# mozilla-try-2019-02-18-zstd-sparse-revlog
before: 81.160994 seconds
after: 37.073753 seconds (-54.32%)
### Compared to 6.4.3
We are still significantly slower than 6.4.3, the extra time is usually twice
slower than the extra time we observe on the locked section, which is a quite
interesting information.
Except for mercurial-central that is much faster. That discrepancy is not really
explained yet.
# mercurial-2018-08-01-zstd-sparse-revlog
6.4.3: 0.072560 seconds
after: 0.105986 seconds (+46.07%) (- 0.03 seconds)
# pypy-2018-08-01-zstd-sparse-revlog
6.4.3: 1.211193 seconds
after: 1.709748 seconds (+41.16%) (-0.45 seconds)
# netbeans-2018-08-01-zstd-sparse-revlog
6.4.3: 4.932843 seconds
after: 7.687469 seconds (+55.84%) (-2.75 seconds)
# mozilla-central-2018-08-01-zstd-sparse-revlog
6.4.3: 34.012226 seconds
after: 17.520316 seconds (-48.49%) (-16.49 seconds)
# mozilla-try-2019-02-18-zstd-sparse-revlog
6.4.3: 23.850555 seconds
after: 37.073753 seconds (+55.44%) (+13.22 seconds)
Pierre-Yves David <pierre-yves.david@octobus.net> [Tue, 30 May 2023 17:43:59 +0100] rev 50671
store: stop relying on a `revlog_type` property
We want to know if a file is related to a revlog, but the rest is dealt with
differently already, so we simplify things further.
as a bonus, this cleanup This provides a small but noticeable speedup.
The number below use `hg perf::stream-locked-section` to measure the time spend
in the locked section of the streaming clone. Number are run on various
repository and compare different steps.:
1) the effect of this patchs,
2) the effect of the cleanup series,
2) current state compared to because large refactoring.
All benchmarks are run on linux with Python 3.10.7.
### Effect of this patch
# mercurial-2018-08-01-zstd-sparse-revlog
# benchmark.name = perf-stream-locked-section
before: 0.030246 seconds
after: 0.029274 seconds (-3.21%)
# pypy-2018-08-01-zstd-sparse-revlog
before: 0.545012 seconds
after: 0.520872 seconds (-4.43%)
# netbeans-2018-08-01-zstd-sparse-revlog
before: 2.719939 seconds
after: 2.626791 seconds (-3.42%)
# mozilla-central-2018-08-01-zstd-sparse-revlog
before: 6.304179 seconds
after: 6.096700 seconds (-3.29%)
# mozilla-try-2019-02-18-zstd-sparse-revlog
before: 14.142687 seconds
after: 13.640779 seconds (-3.55%)
### Effect of this series
A small but sizeable speedup
# mercurial-2018-08-01-zstd-sparse-revlog
before: 0.031122 seconds
after: 0.029274 seconds (-5.94%)
# pypy-2018-08-01-zstd-sparse-revlog
before: 0.589970 seconds
after: 0.520872 seconds (-11.71%)
# netbeans-2018-08-01-zstd-sparse-revlog
before: 2.980300 seconds
after: 2.626791 seconds (-11.86%)
# mozilla-central-2018-08-01-zstd-sparse-revlog
before: 6.863204 seconds
after: 6.096700 seconds (-11.17%)
# mozilla-try-2019-02-18-zstd-sparse-revlog
before: 14.921393 seconds
after: 13.640779 seconds (-8.58%)
### Current state compared to the pre-refactoring state
The refactoring introduced multiple string manipulation and dictionary creation
that seems to induce a signifiant slowdown
Slowdown
# mercurial-2018-08-01-zstd-sparse-revlog
6.4.3: 0.019459 seconds
after: 0.029274 seconds (+50.44%)
## pypy-2018-08-01-zstd-sparse-revlog
6.4.3: 0.290715 seconds
after: 0.520872 seconds (+79.17%)
# netbeans-2018-08-01-zstd-sparse-revlog
6.4.3: 1.403447 seconds
after: 2.626791 seconds (+87.17%)
# mozilla-central-2018-08-01-zstd-sparse-revlog
6.4.3: 3.163549 seconds
after: 6.096700 seconds (+92.72%)
# mozilla-try-2019-02-18-zstd-sparse-revlog
6.4.3: 6.702184 seconds
after: 13.640779 seconds (+103.53%)
Pierre-Yves David <pierre-yves.david@octobus.net> [Tue, 30 May 2023 16:38:13 +0100] rev 50670
store: directly pass the filesize in the `details` of revlog
The dictionary only contains 1 (or 0) entries, we can directly store that
information (or None).
Moving to a simpler argument passing result in a noticable speedup (because
Python)
The number below use `hg perf::stream-locked-section` to measure the time spend
in the locked section of the streaming clone. Number are run on various
repository.
### mercurial-2018-08-01-zstd-sparse-revlog
before: 0.031247 seconds
after: 0.030246 seconds (-3.20%)
### mozilla-central-2018-08-01-zstd-sparse-revlog
before: 6.718968 seconds
after: 6.304179 seconds (-6.17%)
### mozilla-try-2019-02-18-zstd-sparse-revlog
before: 14.631343 seconds
after: 14.142687 seconds (-3.34%)
### netbeans-2018-08-01-zstd-sparse-revlog
before: 2.895584 seconds
after: 2.719939 seconds (-6.07%)
### pypy-2018-08-01-zstd-sparse-revlog
before: 0.561843 seconds
after: 0.543034 seconds (-3.35%)