UNCONFIRMED 76460
Perf improvement via caching Element::styleForRenderer() 
https://bugs.webkit.org/show_bug.cgi?id=76460
Summary Perf improvement via caching Element::styleForRenderer()
Peter Kotwicz
Reported 2012-01-17 08:36:18 PST
styleForRenderer() is a pretty heavy function. In some cases we compute it twice in "Element::recalcStyle" and "NodeRendererFactory::createRendererIfNeeded". NdeRendererFactory is called via Element::attach I have attached a file where this improvement does improve the performance of Element::recalc. For the attached file, the improvement is on the order of 3-4us. On measurements on a reasonably complex page, doing the caching results in a .1 - .5ms improvement in processing Element::recalc
Attachments
test case (192 bytes, text/html)
2012-01-17 11:07 PST, Peter Kotwicz 		no flags
Details
View All Add attachment proposed patch, testcase, etc.
Antti Koivisto
Comment 1 2012-01-17 10:54:45 PST
I'm planning to get rid of NodeRenderingFactory class which just confuses things. Computing the style twice in case of attach() triggered from recalcStyle is indeed a problem that should be fixed.
Peter Kotwicz
Comment 2 2012-01-17 11:07:20 PST
Created attachment 122784 [details] test case
Peter Kotwicz
Comment 3 2012-01-17 13:00:51 PST
I did a bit more measurements. For a reasonable web site, for a page where the recalc is done twice, this produces a performance improvement in Element::recalcStyle of about 1%
Note You need to log in before you can comment on or make changes to this bug.