580491 - Websites with javascript image transitions makes the system unresponsive

Status: RESOLVED WONTFIX

(Core :: Graphics, defect)

Description

[Nathanael Noblet]

User-Agent:       Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10.6; en-US; rv:1.9.2.6) Gecko/20100625 Firefox/3.6.6
Build Identifier: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2.4) Gecko/20100622 Fedora/3.6.4-1.fc13 Firefox/3.6.4

When visiting the url http://www.shopthevillage.ca on linux, the system becomes unresponsive.

I should note that FF running on Windows XP, within a VirtualBox instance on linux does not suffer from the same issue.

I've tried all versions of Firefox (including 4b1)

Reproducible: Always

Steps to Reproduce:
1. Visit http://www.shopthevillage.ca
2.
3.
Actual Results:  
System comes to a crawl until I can finally close the tab.

Expected Results:  
Banner images transition smoothly.

Comment 2

[Karl Tomlinson (:karlt)]

From bug 242364 comment 13:

(Quad Core, 4G RAM, ATI 4670).
 We've isolated the problem to changing opacity on a dynamically
scaled images. Our test site is http://www.shopthevillage.ca/ if we remove the
scaling the transitions are smooth and performance is as expected. Otherwise
during a transition the system is unresponsive for a *long* time. I've tried FF
4B1 with the same effect.

Comment 3

[Karl Tomlinson (:karlt)]

Scaling is done by the X11 graphics drivers so is driver dependent.

Are you using the radeon driver from xf86-video-ati with kms?
This sounds like
https://bugs.freedesktop.org/show_bug.cgi?id=27139

We can work around that by using EXTEND_PAD instead of EXTEND_NONE.  (i.e. undo
our workarounds for bad extend pad.)
Bug 422179 will switch back to extend pad with upscaling.
I think we should also use extend pad for downscaling as GL-supporting video
cards are more likely to support extend pad than extend none.

See also bug 581797 comment 9 and subsequent.

Comment 4

[Nathanael Noblet]

Yes we are using ATI hardware. I will have to double check if we have similar behaviour with an nvidia card, I think it was similar, though perhaps not as noticeable.

Comment 5

[Karl Tomlinson (:karlt)]

"glxinfo | grep OpenGL" will indicate the particular driver used.
I'm interested to hear whether you see similar issues with other drivers.

Comment 6

[Nathanael Noblet]

I can confirm that with an intel card, this behaviour is not happening.

OpenGL vendor string: Tungsten Graphics, Inc
OpenGL renderer string: Mesa DRI Intel(R) IGDNG_M GEM 20100328 2010Q1 
OpenGL version string: 2.1 Mesa 7.8.1
OpenGL shading language version string: 1.20
OpenGL extensions:

Comment 7

[Joe Drew (not getting mail)]

It's usually possible to work around driver bugs, but in this case I don't think we should. We're moving towards Skia, and some point we may also offer a software-only Cairo path, so this will rapidly become not-an-issue.