713992 - -moz-linear-gradient causing significant performance issues in FF9 / Win7

Status: RESOLVED WORKSFORME

(Core :: Graphics, defect)

Description

[A. Lepe]

Attachment: mozback.html

User Agent: Mozilla/5.0 (Ubuntu; X11; Linux i686; rv:8.0) Gecko/20100101 Firefox/8.0
Build ID: 20111115184056

Steps to reproduce:

We are having a great performance issue with Windows 7 and FF9. Having a CSS background composed of 3 linear gradients:

background: -moz-repeating-linear-gradient(left top 0deg, rgba(150, 150, 150, 0.1), transparent 1px, transparent 5px, transparent 6px) repeat scroll 0 0pt,
            -moz-repeating-linear-gradient(left top 47deg, rgba(150, 150, 150, 0.1), transparent 1px, transparent 5px, transparent 6px) repeat scroll 0 0pt,
            -moz-repeating-linear-gradient(left top -47deg, rgba(150, 150, 150, 0.1), transparent 1px, transparent 5px, transparent 6px) repeat scroll 0 0 transparent;

When I remove the background everything is rendered as normal.

Probably related to this bugs:
https://bugzilla.mozilla.org/show_bug.cgi?id=644444
https://bugzilla.mozilla.org/show_bug.cgi?id=672931


Actual results:

It takes up to 10 seconds to display (any other CSS events, like showing or hiding a div over that background using only css, are delayed).

I tested in 3 different computers, all running Windows 7 (tested on 32bits) and the problem is the same. On Windows XP and Linux there is no such problem. 


Expected results:

Should render it without delay as it happens in WinXP and Linux.

Comment 1

[Bas Schouten (:bas.schouten)]

I believe there is already a bug on this. The Azure-Thebes wrapper work should resolve this issue, I'll test this sometime soon, but it won't be fixed 'soon'. Fixing this in the current cairo situation is very hard.

Comment 2

[Alice0775 White]

likely Bug 657603

Comment 3

[(mostly gone) XtC4UaLL [:xtc4uall]]

This is WFM/fixed using Mozilla/5.0 (Windows NT 6.1; WOW64; rv:18.0) Gecko/20100101 Firefox/18.0 ID:20130116073211

Anyone confirm?

Comment 4

[Carlo 'Carcarlo' Carmagnini]

Attachment: linear-gradient on body hangs Firefox

CPU (Intel single core 1.06Ghz) to 100% for 3 seconds. I too think it's related to bug 657603. Other types of linear-gradient make if freeze for longer like the attached one.

Comment 5

[Alice0775 White]

I can reproduce the high CPU usage problem if HWA disabled, but cannot reproduce when HWA enabled.

http://hg.mozilla.org/mozilla-central/rev/52c92a6c6e24
Mozilla/5.0 (Windows NT 6.1; WOW64; rv:21.0) Gecko/20130126 Firefox/21.0 ID:20130126030941

Comment 6

[Gregory Pappas [:gregp]]

This performs very good now.