Bug 63909 – Remove virtual functions from StyleImage.

• Status: RESOLVED
• Resolution: FIXED
• Component: CSS

[Tamas Czene]

We can remove the virtual "isChachedImage, isPendingImage, isGeneratedImage" functions to speed up the StyleImage part of WebKit.
Some profile data shows this part is significant, especially in small CSS-based sites.
Removing the virtual functions - removing the calls - makes a small performance progression on this part.

We measured around 1% speed up on several sites like: bing.com , youtube.com

[Tamas Czene]

Created attachment 99632 [details]
Remove virtual functions from StyleImage

[Tamas Czene]

Created attachment 99675 [details]
Remove virtual functions from StyleImage

[Simon Fraser (smfr)]

Comment on attachment 99675 [details]
Remove virtual functions from StyleImage

View in context: https://bugs.webkit.org/attachment.cgi?id=99675&action=review

> Source/WebCore/ChangeLog:10
> +        Some profile data shows this part is significant, especially in small CSS-based sites.
> +        Removing the virtual functions - removing the calls - makes a small performance progression on this part.

You should put more information in the bug about your performance investigations. What sites did you test? What as the measured gain? What stack traces show time in these methods?

[WebKit Review Bot]

Comment on attachment 99675 [details]
Remove virtual functions from StyleImage

Clearing flags on attachment: 99675

Committed r90399: <http://trac.webkit.org/changeset/90399>

[WebKit Review Bot]

All reviewed patches have been landed.  Closing bug.

[Tamas Czene]

Generally the effect of the patch is only measurable on small sites.
Examples (Methanol results): 
bing.com  2,6% 
wordpress.org 5,7%