1356091 - Allow software backed compositor process (behind a preference)

Status: RESOLVED FIXED

(Core :: Graphics, enhancement)

Description

[Milan Sreckovic [:milan] (needinfo for best results)]

Right now we insist on an accelerated compositor when deciding if we want a compositor process or not.  Behind a preference, allow the software backend and compositor process combination.

Comment 1

[Milan Sreckovic [:milan] (needinfo for best results)]

http://searchfox.org/mozilla-central/source/gfx/thebes/gfxWindowsPlatform.cpp#1577

Comment 2

[Milan Sreckovic [:milan] (needinfo for best results)]

We do have layers.gpu-process.force-enabled preference, but that is a bit too strong.

Comment 3

[Milan Sreckovic [:milan] (needinfo for best results)]

Attachment: Bug 1356091: Allow the compositor process with the software compositor.

Review commit: https://reviewboard.mozilla.org/r/129724/diff/#index_header
See other reviews: https://reviewboard.mozilla.org/r/129724/

Comment 4

[David Anderson [:dvander] - inactive, e-mail if emergency]

Comment on attachment 8857756 [details]
Bug 1356091: Allow the compositor process with the software compositor.

https://reviewboard.mozilla.org/r/129724/#review132354

Comment 5

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/cb9c72e4a639
Allow the compositor process with the software compositor. r=dvander

Comment 6

[Milan Sreckovic [:milan] (needinfo for best results)]

Comment on attachment 8857756 [details]
Bug 1356091: Allow the compositor process with the software compositor.

Approval Request Comment
This introduces a preference, and allows software compositor in the compositor process when that preference is set - which it isn't by default.  So, the change as such is a no-op and thus of very low (zero :) risk.
Why do we want it?  There are some indications that there may be performance improvements with the compositor process (bug 1334655), not just the stability when it comes to the drivers.  If this is the case, well, things are good.

We'd like to be able to run some telemetry experiments with 54 on aurora/beta, which is what this change/preference would allow us to do.

Comment 7

[Wes Kocher (:KWierso) (Not reading bugmail; email directly if needed)]

https://hg.mozilla.org/mozilla-central/rev/cb9c72e4a639

Comment 8

[Milan Sreckovic [:milan] (needinfo for best results)]

It'd be interesting to see if this nudges Talos in one direction or another on Windows non-accelerated backend(s)

Comment 9

[Milan Sreckovic [:milan] (needinfo for best results)]

(In reply to Milan Sreckovic [:milan] from comment #8)
> It'd be interesting to see if this nudges Talos in one direction or another
> on Windows non-accelerated backend(s)

Uhm, of course it shouldn't, because it is off by default.

Comment 10

[Gerry Chang [:gchang]]

Comment on attachment 8857756 [details]
Bug 1356091: Allow the compositor process with the software compositor.

There might be performance improvement here. Aurora54+.

Comment 11

[Ryan VanderMeulen [:RyanVM]]

https://hg.mozilla.org/releases/mozilla-aurora/rev/fc6add581f88