Mercurial > hg
view tests/test-empty-file.t @ 35599:af25237be091
perf: add threading capability to perfbdiff
Since we are releasing the GIL during diffing, it is interesting to see how a
thread pool would perform on diffing. We add a new `--threads` argument to
commands. Synchronizing the thread pool is a bit complex because we want to be
able to reuse it from one run to another.
On my computer (i7 with 4 cores + hyperthreading), I get the following data for
about 12000 revisions:
threads wall comb wall gain comb overhead
none 31.596715 31.59 0.00% 0.00%
1 31.621228 31.62 -0.08% 0.09%
2 16.406202 32.8 48.08% 3.83%
3 11.598334 34.76 63.29% 10.03%
4 9.205421 36.77 70.87% 16.40%
5 8.517604 42.51 73.04% 34.57%
6 7.94645 47.58 74.85% 50.62%
7 7.434972 51.92 76.47% 64.36%
8 7.070638 55.34 77.62% 75.18%
Compared to the feature disabled (threads=0), the overhead is negligible with
the threading code (threads=1), and the gain is already 48% with two threads.
author | Boris Feld <boris.feld@octobus.net> |
---|---|
date | Sun, 17 Dec 2017 04:31:27 +0100 |
parents | f2719b387380 |
children |
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$ hg init a $ cd a $ touch empty1 $ hg add empty1 $ hg commit -m 'add empty1' $ touch empty2 $ hg add empty2 $ hg commit -m 'add empty2' $ hg up -C 0 0 files updated, 0 files merged, 1 files removed, 0 files unresolved $ touch empty3 $ hg add empty3 $ hg commit -m 'add empty3' created new head $ hg heads changeset: 2:a1cb177e0d44 tag: tip parent: 0:1e1d9c4e5b64 user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: add empty3 changeset: 1:097d2b0e17f6 user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: add empty2 $ hg merge 1 1 files updated, 0 files merged, 0 files removed, 0 files unresolved (branch merge, don't forget to commit) Before changeset 05257fd28591, we didn't notice the empty file that came from rev 1: $ hg status M empty2 $ hg commit -m merge $ hg manifest --debug tip b80de5d138758541c5f05265ad144ab9fa86d1db 644 empty1 b80de5d138758541c5f05265ad144ab9fa86d1db 644 empty2 b80de5d138758541c5f05265ad144ab9fa86d1db 644 empty3 $ cd ..