Bug 134879

Summary: [iOS] Throttle painting using a UI-process-side CADisplayLink
Product: WebKit Reporter: Tim Horton <thorton>
Component: WebKit2Assignee: Tim Horton <thorton>
Status: RESOLVED FIXED    
Severity: Normal CC: barraclough, simon.fraser
Priority: P2 Keywords: InRadar
Version: 528+ (Nightly build)   
Hardware: Unspecified   
OS: Unspecified   
Attachments:
Description Flags
patch simon.fraser: review+

Description Tim Horton 2014-07-13 19:30:07 PDT 
Just waiting for CA to "commit" in the UI process isn't enough, because we still aren't throttled to 60fps, because the UI process runloop is just happily looping away.

Let's use a CADisplayLink and actually throttle the didUpdate reply to 60fps, thus throttling painting (often only barely makes 60fps anyway) and requestAnimationFrame (much more problematic).

<rdar://problem/17641699>
Comment 1 Tim Horton 2014-07-13 21:58:19 PDT 
Created attachment 234840 [details]
patch
Comment 2 Simon Fraser (smfr) 2014-07-14 10:22:15 PDT 
Comment on attachment 234840 [details]
patch

View in context: https://bugs.webkit.org/attachment.cgi?id=234840&action=review

> Source/WebKit2/UIProcess/mac/RemoteLayerTreeDrawingAreaProxy.mm:67
> +        _displayLink.paused = true;

YES
Comment 3 Tim Horton 2014-07-14 11:12:29 PDT 
http://trac.webkit.org/changeset/171068