Mercurial > hg
view tests/test-obsolete-tag-cache.t @ 44363:f7459da77f23
nodemap: introduce an option to use mmap to read the nodemap mapping
The performance and memory benefit is much greater if we don't have to copy all
the data in memory for each information. So we introduce an option (on by
default) to read the data using mmap.
This changeset is the last one definition the API for index support nodemap
data. (they have to be able to use the mmaping).
Below are some benchmark comparing the best we currently have in 5.3 with the
final step of this series (using the persistent nodemap implementation in
Rust). The benchmark run `hg perfindex` with various revset and the following
variants:
Before:
* do not use the persistent nodemap
* use the CPython implementation of the index for nodemap
* use mmapping of the changelog index
After:
* use the MixedIndex Rust code, with the NodeTree object for nodemap access
(still in review)
* use the persistent nodemap data from disk
* access the persistent nodemap data through mmap
* use mmapping of the changelog index
The persistent nodemap greatly speed up most operation on very large
repositories. Some of the previously very fast lookup end up a bit slower because
the persistent nodemap has to be setup. However the absolute slowdown is very
small and won't matters in the big picture.
Here are some numbers (in seconds) for the reference copy of mozilla-try:
Revset Before After abs-change speedup
-10000: 0.004622 0.005532 0.000910 × 0.83
-10: 0.000050 0.000132 0.000082 × 0.37
tip 0.000052 0.000085 0.000033 × 0.61
0 + (-10000:) 0.028222 0.005337 -0.022885 × 5.29
0 0.023521 0.000084 -0.023437 × 280.01
(-10000:) + 0 0.235539 0.005308 -0.230231 × 44.37
(-10:) + :9 0.232883 0.000180 -0.232703 ×1293.79
(-10000:) + (:99) 0.238735 0.005358 -0.233377 × 44.55
:99 + (-10000:) 0.317942 0.005593 -0.312349 × 56.84
:9 + (-10:) 0.313372 0.000179 -0.313193 ×1750.68
:9 0.316450 0.000143 -0.316307 ×2212.93
On smaller repositories, the cost of nodemap related operation is not as big, so
the win is much more modest. Yet it helps shaving a handful of millisecond here
and there.
Here are some numbers (in seconds) for the reference copy of mercurial:
Revset Before After abs-change speedup
-10: 0.000065 0.000097 0.000032 × 0.67
tip 0.000063 0.000078 0.000015 × 0.80
0 0.000561 0.000079 -0.000482 × 7.10
-10000: 0.004609 0.003648 -0.000961 × 1.26
0 + (-10000:) 0.005023 0.003715 -0.001307 × 1.35
(-10:) + :9 0.002187 0.000108 -0.002079 ×20.25
(-10000:) + 0 0.006252 0.003716 -0.002536 × 1.68
(-10000:) + (:99) 0.006367 0.003707 -0.002660 × 1.71
:9 + (-10:) 0.003846 0.000110 -0.003736 ×34.96
:9 0.003854 0.000099 -0.003755 ×38.92
:99 + (-10000:) 0.007644 0.003778 -0.003866 × 2.02
Differential Revision: https://phab.mercurial-scm.org/D7894
author | Pierre-Yves David <pierre-yves.david@octobus.net> |
---|---|
date | Tue, 11 Feb 2020 11:18:52 +0100 |
parents | 34a46d48d24e |
children | 011f5218ff2d |
line wrap: on
line source
$ cat >> $HGRCPATH << EOF > [extensions] > blackbox= > rebase= > mock=$TESTDIR/mockblackbox.py > > [blackbox] > track = command, commandfinish, tagscache > > [experimental] > evolution.createmarkers=True > EOF Create a repo with some tags $ hg init repo $ cd repo $ echo initial > foo $ hg -q commit -A -m initial $ hg tag -m 'test tag' test1 $ echo first > first $ hg -q commit -A -m first $ hg tag -m 'test2 tag' test2 $ hg -q up -r 0 $ echo newhead > newhead $ hg commit -A -m newhead adding newhead created new head $ hg tag -m 'test head 2 tag' head2 $ hg log -G -T '{rev}:{node|short} {tags} {desc}\n' @ 5:2942a772f72a tip test head 2 tag | o 4:042eb6bfcc49 head2 newhead | | o 3:c3cb30f2d2cd test2 tag | | | o 2:d75775ffbc6b test2 first | | | o 1:5f97d42da03f test tag |/ o 0:55482a6fb4b1 test1 initial Trigger tags cache population by doing something that accesses tags info $ hg tags tip 5:2942a772f72a head2 4:042eb6bfcc49 test2 2:d75775ffbc6b test1 0:55482a6fb4b1 $ cat .hg/cache/tags2-visible 5 2942a772f72a444bef4bef13874d515f50fa27b6 042eb6bfcc4909bad84a1cbf6eb1ddf0ab587d41 head2 55482a6fb4b1881fa8f746fd52cf6f096bb21c89 test1 d75775ffbc6bca1794d300f5571272879bd280da test2 Hiding a non-tip changeset should change filtered hash and cause tags recompute $ hg debugobsolete -d '0 0' c3cb30f2d2cd0aae008cc91a07876e3c5131fd22 -u dummyuser 1 new obsolescence markers obsoleted 1 changesets $ hg tags tip 5:2942a772f72a head2 4:042eb6bfcc49 test1 0:55482a6fb4b1 $ cat .hg/cache/tags2-visible 5 2942a772f72a444bef4bef13874d515f50fa27b6 f34fbc9a9769ba9eff5aff3d008a6b49f85c08b1 042eb6bfcc4909bad84a1cbf6eb1ddf0ab587d41 head2 55482a6fb4b1881fa8f746fd52cf6f096bb21c89 test1 $ hg blackbox -l 5 1970/01/01 00:00:00 bob @2942a772f72a444bef4bef13874d515f50fa27b6 (5000)> tags 1970/01/01 00:00:00 bob @2942a772f72a444bef4bef13874d515f50fa27b6 (5000)> 2/2 cache hits/lookups in * seconds (glob) 1970/01/01 00:00:00 bob @2942a772f72a444bef4bef13874d515f50fa27b6 (5000)> writing .hg/cache/tags2-visible with 2 tags 1970/01/01 00:00:00 bob @2942a772f72a444bef4bef13874d515f50fa27b6 (5000)> tags exited 0 after * seconds (glob) 1970/01/01 00:00:00 bob @2942a772f72a444bef4bef13874d515f50fa27b6 (5000)> blackbox -l 5 Hiding another changeset should cause the filtered hash to change $ hg debugobsolete -d '0 0' d75775ffbc6bca1794d300f5571272879bd280da -u dummyuser 1 new obsolescence markers obsoleted 1 changesets $ hg debugobsolete -d '0 0' 5f97d42da03fd56f3b228b03dfe48af5c0adf75b -u dummyuser 1 new obsolescence markers obsoleted 1 changesets $ hg tags tip 5:2942a772f72a head2 4:042eb6bfcc49 $ cat .hg/cache/tags2-visible 5 2942a772f72a444bef4bef13874d515f50fa27b6 2fce1eec33263d08a4d04293960fc73a555230e4 042eb6bfcc4909bad84a1cbf6eb1ddf0ab587d41 head2 $ hg blackbox -l 5 1970/01/01 00:00:00 bob @2942a772f72a444bef4bef13874d515f50fa27b6 (5000)> tags 1970/01/01 00:00:00 bob @2942a772f72a444bef4bef13874d515f50fa27b6 (5000)> 1/1 cache hits/lookups in * seconds (glob) 1970/01/01 00:00:00 bob @2942a772f72a444bef4bef13874d515f50fa27b6 (5000)> writing .hg/cache/tags2-visible with 1 tags 1970/01/01 00:00:00 bob @2942a772f72a444bef4bef13874d515f50fa27b6 (5000)> tags exited 0 after * seconds (glob) 1970/01/01 00:00:00 bob @2942a772f72a444bef4bef13874d515f50fa27b6 (5000)> blackbox -l 5 Resolving tags on an unfiltered repo writes a separate tags cache $ hg --hidden tags tip 5:2942a772f72a head2 4:042eb6bfcc49 test2 2:d75775ffbc6b test1 0:55482a6fb4b1 $ cat .hg/cache/tags2 5 2942a772f72a444bef4bef13874d515f50fa27b6 042eb6bfcc4909bad84a1cbf6eb1ddf0ab587d41 head2 55482a6fb4b1881fa8f746fd52cf6f096bb21c89 test1 d75775ffbc6bca1794d300f5571272879bd280da test2 $ hg blackbox -l 5 1970/01/01 00:00:00 bob @2942a772f72a444bef4bef13874d515f50fa27b6 (5000)> --hidden tags 1970/01/01 00:00:00 bob @2942a772f72a444bef4bef13874d515f50fa27b6 (5000)> 2/2 cache hits/lookups in * seconds (glob) 1970/01/01 00:00:00 bob @2942a772f72a444bef4bef13874d515f50fa27b6 (5000)> writing .hg/cache/tags2 with 3 tags 1970/01/01 00:00:00 bob @2942a772f72a444bef4bef13874d515f50fa27b6 (5000)> --hidden tags exited 0 after * seconds (glob) 1970/01/01 00:00:00 bob @2942a772f72a444bef4bef13874d515f50fa27b6 (5000)> blackbox -l 5