view tests/test-diff-hashes.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 251332dbf33d
line wrap: on
line source

  $ hg init a
  $ cd a

  $ hg diff inexistent1 inexistent2
  inexistent1: * (glob)
  inexistent2: * (glob)

  $ echo bar > foo
  $ hg add foo
  $ hg ci -m 'add foo'

  $ echo foobar > foo
  $ hg ci -m 'change foo'

  $ hg --quiet diff -r 0 -r 1
  --- a/foo	Thu Jan 01 00:00:00 1970 +0000
  +++ b/foo	Thu Jan 01 00:00:00 1970 +0000
  @@ -1,1 +1,1 @@
  -bar
  +foobar

  $ hg diff -r 0 -r 1
  diff -r a99fb63adac3 -r 9b8568d3af2f foo
  --- a/foo	Thu Jan 01 00:00:00 1970 +0000
  +++ b/foo	Thu Jan 01 00:00:00 1970 +0000
  @@ -1,1 +1,1 @@
  -bar
  +foobar

  $ hg --verbose diff -r 0 -r 1
  diff -r a99fb63adac3 -r 9b8568d3af2f foo
  --- a/foo	Thu Jan 01 00:00:00 1970 +0000
  +++ b/foo	Thu Jan 01 00:00:00 1970 +0000
  @@ -1,1 +1,1 @@
  -bar
  +foobar

  $ hg --debug diff -r 0 -r 1
  diff -r a99fb63adac3f31816a22f665bc3b7a7655b30f4 -r 9b8568d3af2f1749445eef03aede868a6f39f210 foo
  --- a/foo	Thu Jan 01 00:00:00 1970 +0000
  +++ b/foo	Thu Jan 01 00:00:00 1970 +0000
  @@ -1,1 +1,1 @@
  -bar
  +foobar

  $ cd ..