2000149 - Let WebRender layer compositor ride the trains to release on Windows

Status: RESOLVED FIXED

(Core :: Graphics: WebRender, task)

Comment 1

[Sotaro Ikeda [:sotaro]]

Attachment: Bug 2000149 - Let WebRender layer compositor ride the trains to release on Windows

Comment 2

[Pulsebot]

Pushed by [e-mail]:
https://github.com/mozilla-firefox/firefox/commit/6f26cb765790
https://hg.mozilla.org/integration/autoland/rev/6b7aa60a1fd5
Let WebRender layer compositor ride the trains to release on Windows r=gfx-reviewers,lsalzman

Comment 3

[Sandor Molnar[:smolnar]]

https://hg.mozilla.org/mozilla-central/rev/6b7aa60a1fd5

Comment 4

[Pulsebot]

Pushed by [e-mail]:
https://github.com/mozilla-firefox/firefox/commit/cbafe46ac95f
https://hg.mozilla.org/integration/autoland/rev/9f6a8d0d5d46
Revert "Bug 2000149 - Let WebRender layer compositor ride the trains to release on Windows r=gfx-reviewers,lsalzman" for causing Bug 2001612.

Comment 5

[Atila Butkovits]

Backed out as requested: https://hg-edge.mozilla.org/integration/autoland/rev/9f6a8d0d5d46cc03884cbee564ba1c9deccdb82b

Comment 6

[Cosmin Sabou [:CosminS]]

Backout merged to central: https://hg.mozilla.org/mozilla-central/rev/9f6a8d0d5d46cc03884cbee564ba1c9deccdb82b

Comment 7

[Acasandrei Beatrice (needinfo me)]

(In reply to Atila Butkovits from comment #5)

Backed out as requested: https://hg-edge.mozilla.org/integration/autoland/rev/9f6a8d0d5d46cc03884cbee564ba1c9deccdb82b

Perfherder has detected a browsertime performance change from push 9f6a8d0d5d46cc03884cbee564ba1c9deccdb82b.

No action is required from the author; this comment is provided for informational purposes only.

Regressions:

Ratio	Test	Platform	Options	Absolute values (old vs new)	Performance Profiles
19%	speedometer VueJS-TodoMVC/CompletingAllItems/Sync	windows11-64-24h2-nightlyasrelease	fission webrender	0.65 -> 0.77	Before/After
19%	speedometer Preact-TodoMVC/CompletingAllItems/Sync	windows11-64-24h2-nightlyasrelease	fission webrender	0.82 -> 0.97	Before/After

Improvements:

Ratio	Test	Platform	Options	Absolute values (old vs new)	Performance Profiles
13%	speedometer Angular2-TypeScript-TodoMVC/CompletingAllItems/Async	windows11-64-24h2-nightlyasrelease	fission webrender	1.22 -> 1.07	Before/After
10%	speedometer Elm-TodoMVC/Adding100Items/Sync	windows11-64-24h2-nightlyasrelease	fission webrender	29.85 -> 26.94	Before/After
10%	speedometer Elm-TodoMVC/Adding100Items	windows11-64-24h2-nightlyasrelease	fission webrender	32.15 -> 29.08	Before/After
10%	speedometer Preact-TodoMVC/Adding100Items/Sync	windows11-64-24h2-nightlyasrelease	fission webrender	0.71 -> 0.64	Before/After

Need Help or Information?

If you have any questions, please reach out to [e-mail]. Alternatively, you can find help on Slack by joining #perf-help, and on Matrix you can find help by joining #perftest.

Details of the alert can be found in the alert summary, including links to graphs and comparisons for each of the affected tests.

Comment 8

[Sotaro Ikeda [:sotaro]]

From Bug 2001612 comment 5,

---

When I look at the graphs on that page it seems like a clear regression to me.

If we're going to regress we should try to have a theory of why and understand what the trade offs are.

The only thing I recall seeing about the advantages was this message from Glenn:
We have initial measurements only from the prototype (where we saw ~20% savings in power usage during video playback). We haven't measured with the merged implementation yet.

We should at least have something more concrete if we're going to accept the regression.

Comment 9

[Sotaro Ikeda [:sotaro]]

Compared the power consumption during video playback measured using an actual power meter. Got around 10% power savings during fullscreen video playback like the following.

• PC1 intel GPU
  • Firefox Nightly with layer compositor: 29 - 30 W
  • Firefox Nightly with native compositor: 32 - 35 W
  • Chrome: 23 - 25 W
• PC2 intel GPU
  • Firefox Nightly with layer compositor: 15 - 16 W
  • Firefox Nightly with native compositor: 17 - 18 W
  • Chrome: 15 - 16 W
• PC3 AMD GPU
  • Firefox Nightly with layer compositor: 11 - 12 W
  • Firefox Nightly with native compositor: 12 - 13 W
  • Chrome: 11 - 12 W

Comment 10

[Sotaro Ikeda [:sotaro]]

Then with layer compositor, we could get the following advantages.

• Save around 10% power during fullscreen video playback as in comment 9.
• Improve WebGL performance by using RGB overlay(Bug 1958603, Bug 2008399)
  • The WebGL overlay improved Talos' glterrain score about 12% with layer compositor.
  • https://perf.compare/compare-results?baseRev=6130de6c5b32f6ff1da0924b47a7009072806f44&baseRepo=try&newRev=3f4d51cf8f5541b73a9a544952ac02fdf7bcdc4a&newRepo=try&framework=1

Comment 11

[Sotaro Ikeda [:sotaro]]

:jrmuizel, can comment 10 be enough benefit of layer compositor?

Comment 12

[Sotaro Ikeda [:sotaro]]

(In reply to Sotaro Ikeda [:sotaro] from comment #11)

:jrmuizel, can comment 10 be enough benefit of layer compositor?

:jrmuizel answered like the following.

---

yeah, that's somewhat compelling

Comment 13

[Pulsebot]

Pushed by [e-mail]:
https://github.com/mozilla-firefox/firefox/commit/4294a1440f30
https://hg.mozilla.org/integration/autoland/rev/b184b5ea2fe4
Let WebRender layer compositor ride the trains to release on Windows r=gfx-reviewers,lsalzman

Comment 14

[Iulian Moraru]

https://hg.mozilla.org/mozilla-central/rev/b184b5ea2fe4

Comment 15

[Pascal Chevrel:pascalc]

Is that something that should be mentioned in our 149 release notes? Thanks.

Comment 16

[Sotaro Ikeda [:sotaro]]

(In reply to Pascal Chevrel:pascalc from comment #15)

Is that something that should be mentioned in our 149 release notes? Thanks.

Yes.

Comment 17

[Sotaro Ikeda [:sotaro]]

Release Note Request (optional, but appreciated)
[Why is this notable]: WebRender rendering is changed from native compositor to layer compositor. It could reduce power usage of fullscreen video playback. And it could improve WebGL/WebGPU performance.
[Affects Firefox for Android]: No
[Suggested wording]: WebRender layer compositor is enabled on Windows. It may affect to WebRender performance.
[Links (documentation, blog post, etc)]:

Comment 18

[Pascal Chevrel:pascalc]

Note added with this wording:

The WebRender layer compositor is now enabled on Windows, reducing power usage during full-screen video playback and improving WebGL/WebGPU performance.

I am keeping the relnote-firefox? flag open until we ship and include that in the final notes. Thanks