[PATCH 1 of 2 obs-speedup] obsolete: add C implementation of _addsuccessors

[Augie Fackler]

On Tue, Aug 25, 2015 at 4:52 PM, Matt Mackall <mpm at selenic.com> wrote:
> On Mon, 2015-08-24 at 14:25 -0400, Augie Fackler wrote:
>> # HG changeset patch
>> # User Augie Fackler <augie at google.com>
>> # Date 1440439282 14400
>> #      Mon Aug 24 14:01:22 2015 -0400
>> # Node ID 3aecfdbfe3ca54134cdb0e98944e8fca53bd46f1
>> # Parent  207e95720308518aa40c2a91ce20fdf52dfa8550
>> obsolete: add C implementation of _addsuccessors
>>
>> Before, best of 10 runs:
>> hg sl > /dev/null  0.75s user 0.07s system 99% cpu 0.828 total
>>
>> After, best of 10 runs:
>> ./hg sl > /dev/null  0.65s user 0.09s system 99% cpu 0.744 total
>>
>> where
>> alias.sl=log -Gr smart -Tsl
>> revsetalias.smart=(parents(not public()) or not public() or . or head()) and (not obsolete() or unstable()^)
>>
>> It's a straight-line port to C code, but still a 10% win on walltime
>> for the command. I can live with that.
>
> I'm kind of loathe to accept C code that isn't at least 4x or so faster
> than what it's replacing, but this 10% doesn't measure that directly.
> Can I get you to tweak perf.py to do that?

If my perf patch is right, this code didn't make much difference.

Before:
! wall 0.074395 comb 0.080000 user 0.070000 sys 0.010000 (best of 100)

After:
! wall 0.067937 comb 0.070000 user 0.070000 sys 0.000000 (best of 100)

So I guess we must be calling addsuccessors a lot of times or something.

diff --git a/contrib/perf.py b/contrib/perf.py
--- a/contrib/perf.py
+++ b/contrib/perf.py
@@ -576,3 +576,10 @@ def perfloadmarkers(ui, repo):
     timer, fm = gettimer(ui)
     timer(lambda: len(obsolete.obsstore(repo.svfs)))
     fm.end()
+
+ at command('perfaddsuccessors')
+def perfaddsuccessors(ui, repo):
+    timer, fm = gettimer(ui)
+    o = repo.obsstore
+    timer(lambda : obsolete._addsuccessors({}, o._all) or len(o))
+    fm.end()


is the perf patch, in case anything is obviously wrong there.

>
> --
> Mathematics is the supreme nostalgia of our time.
>