1420433 - We sometimes build the scene several times before rendering

Status: RESOLVED FIXED

(Core :: Graphics: WebRender, enhancement, P3)

Description

[Nicolas Silva [:nical]]

WebRender currently does not have a way to group updating several pipelines into a single transaction, which means that we sometimes cause the scene to be built several times before we render it.

There's a PR currently on hold to add a more flexible transaction based API https://github.com/servo/webrender/pull/1963 that would need a bit of work to be rebased. If it doesn't get prioritized now I'll probably work on it in January.

I am not sure whether unfortunate timings causing us to rebuild scenes several times happen often in the cases that we care about in the very short term, it seems to be facilitated by the presence of video elements since they have their own pipelines (although are not intended to often cause scenes to be rebuilt).

It would be good to at least add some instrumentation/warnings to better see how much this problem occurs and where.

Comment 1

[Jeff Muizelaar [:jrmuizel]]

Should this still be open?