Bug 145465 – Consider throttling DOM timers in iframes outside the viewport

• Status: RESOLVED
• Resolution: FIXED
• Component: DOM

[Chris Dumez]

Consider throttling DOM timers in iframe outside the viewport for performance and power reasons.

Radar: <rdar://problem/20768957>

[Chris Dumez]

Created attachment 253910 [details]
Patch

[Geoffrey Garen]

Comment on attachment 253910 [details]
Patch

What if the iframe has <audio> or is using the WebAudio API?

[Chris Dumez]

(In reply to comment #2)
> Comment on attachment 253910 [details]
> Patch
> 
> What if the iframe has <audio> or is using the WebAudio API?

First of all, audio would only be a problem here is audio is somehow driven by timers.
I don't know if there is content doing this but it seems unlikely to me because there is no guarantee your timer will fire *when* you ask it to. It all depends on the load of the system / browser.

Also note that we already throttle timers in background pages and I use the same mechanism here for out-of-viewport iframes. So timer-driven audio would likely already be broken in the case of background pages.

If this turns out to be an issue, we could restrict the throttling to cross-origin iframes for example.

[WebKit Commit Bot]

Comment on attachment 253910 [details]
Patch

Clearing flags on attachment: 253910

Committed r185012: <http://trac.webkit.org/changeset/185012>

[WebKit Commit Bot]

All reviewed patches have been landed.  Closing bug.