Bug 234006 – ANGLE Metal stencil, depth, multisample performance regression

• Status: NEW
• Component: WebGL

[Jekfer Bichon]

Created attachment 446362 [details]
Sample to reproduce

Hello,

We have detected a performance regression on Safari 15 when using "antialias: true" option on the WebGLRendering context. The regression was detected on an iPad Gen 8.

I have attached a sample to reproduce the issue, on portrait mode. On Safari 14 we were getting an average of 58-59 fps on the sample, meanwhile Safari 15 runs around 36 fps. Disabling the experimental option "WebGL via Metal" on Safari 15 puts the performances back at Safari 14 level.
The portrait/landscape mode is not very important to the issue at hand, the quad on the sample was simply positioned in a way to occupy most of the screen on portrait mode.

Thank you.

[Radar WebKit Bug Importer]

<rdar://problem/86523176>

[Kimmo Kinnunen]

Thank you for the report.
I can reproduce the issue.

[Kimmo Kinnunen]

Note: The test case is also setting up canvas with four times the screen size with antialias: true, stencil:true, depth:true, so the default framebuffer consumes quite much memory (100+gb) and jetsams on some devices.

[Sébastien VIDECOQ]

Hello, any progress on this ? This is severely impacting performances of our products.

[Kimmo Kinnunen]

(In reply to Sébastien VIDECOQ from comment #4)
> Hello, any progress on this ? This is severely impacting performances of our
> products.

Thanks for the query.
Currently I cannot reproduce this on iPad Pro 2020, iOS 15.4 seed 4. I'll try with other devices later.

If you have time, please update to iOS 15.4 seed 4 or later and retry on your end.