951255 - canvasmark 3.21% regression on windows xp starting december 11th

Status: RESOLVED DUPLICATE of bug 950264

(Testing :: Talos, defect)

Description

[Joel Maher ( :jmaher ) (UTC -8)]

as found on dev.tree-management:
https://groups.google.com/forum/#!topic/mozilla.dev.tree-management/Kt6dp07ZA3w

datazilla link:
https://datazilla.mozilla.org/?start=1386214400&stop=1387020996&product=Firefox&repository=Mozilla-Inbound-Non-PGO&test=tcanvasmark&page=Asteroids%20-%20Bitmaps-%20shapes-%20text&graph_search=1390f263b8ce&x86=true&x86_64=false&error_bars=false&project=talos

graph server link:
http://graphs.mozilla.org/graph.html#tests=[[297,131,37]]&sel=none&displayrange=7&datatype=running

canvasmark is taken from:
http://www.kevs3d.co.uk/dev/canvasmark/

I did some retriggers on inbound and it looks that bug 773296 is the culprit.  There were a lot of patches (a series for that bug) which landed.  We only affect the Asteroids - Bitmaps- shapes- text:
http://hg.mozilla.org/build/talos/file/2bcf422011d1/talos/page_load_test/canvasmark/scripts/canvasmark_v6.js#l1471

I am not sure exactly what that does, but maybe :snorp could help us figure it out.

Comment 1

[James Willcox (:snorp) ([e-mail]) (he/him)]

(In reply to Joel Maher (:jmaher) from comment #0)
> I am not sure exactly what that does, but maybe :snorp could help us figure
> it out.

It's a variety of canvas stuff. It draws some arcs, images, text, etc.

Comment 2

[Cameron McCormack (:heycam)]

I've been trying to narrow down which part of the big patch queue would have caused this in bug 950264.  Sounds like it would be the text part of that canvasmark subtest, since setting the font on a canvas will do some style resolution.

Comment 3

[Joel Maher ( :jmaher ) (UTC -8)]

we could easily push to try and see if that changes the numbers.  I assume we can't just back out parts of the patches.

Comment 4

[Cameron McCormack (:heycam)]

Yes, I've identified part of the regression in but 950264 comment 1 by doing that.  Unfortunately that patch is reasonably simple and I'm not sure if there's a way it could be rewritten to help.

Comment 5

[Joel Maher ( :jmaher ) (UTC -8)]

good news is this doesn't affect other platforms, marking as a dup of 950264