Mercurial > hg
view tests/test-empty-file.t @ 41247:a89b20a49c13
rust-cpython: using MissingAncestors from Python code
As precedently done with LazyAncestors on cpython.rs, we test for the
presence of the 'rustext' module.
incrementalmissingrevs() has two callers within the Mercurial core:
`setdiscovery.partialdiscovery` and the `only()` revset.
This move shows a significant discovery performance improvement
in cases where the baseline is slow: using perfdiscovery on the PyPy
repos, prepared with `contrib/discovery-helper <repo> 50 100`, we
get averaged medians of 403ms with the Rust version vs 742ms without
(about 45% better).
But there are still indications that performance can be worse in cases
the baseline is fast, possibly due to the conversion from Python to
Rust and back becoming the bottleneck. We could measure this on
mozilla-central in cases were the delta is just a few changesets.
This requires confirmation, but if that's the reason, then an
upcoming `partialdiscovery` fully in Rust should solve the problem.
Differential Revision: https://phab.mercurial-scm.org/D5551
author | Georges Racinet <georges.racinet@octobus.net> |
---|---|
date | Fri, 30 Nov 2018 14:35:57 +0100 |
parents | f2719b387380 |
children |
line wrap: on
line source
$ 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 ..