Gmaps WebGL + UI freeze with VulkanFromANGLE

[Damien Mfaransa]

Hello Angle team,

Trying to break down some behavior i've been experiencing using Google Maps (WebGL) on Chromium, which produces noticeable UI freezes.

To trigger this behavior :

- launch Chrome/ium with features : Vulkan,DefaultANGLEVulkan,VulkanFromANGLE
- navigate to Google Maps
- switch to "Satellite view" + 3D View / Globe view (advanced Web GL ?)
- start dragging map + release while still moving pointer
=> maps starts scrolling animation
- switch to other chromium tab before scrolling animation ends

=> when (invisible) animation ends in background, Google Maps engine is obviously doing something wrong :

- a storm of 500K to 1.5M WebGL calls is issued, probably as much as CPU can produce before some timeout
- occurs only when animation ends while visibilityState = hidden
- at the end no visible change on Maps display despite high number of GL calls issued

=> if VulkanFromANGLE is active, while (bogus?) WebGL calls are processed, the UI shows severe responsiveness issues if not total freeze for up to several seconds.
=> if VulkanFromANGLE is omitted, no such UI lag is noticeable
Interesting fact, the more CPU available, the more severe the effect is.

Regarding the described issue, it is likely some kind of bug in google maps engine. 

However, it shows that navigation to a non-optimal WebGL site can affect the entire Chromium/ANGLE context.

What is your position on such matter ? Maybe some kind of "throttling" or priority inside ANGLE would help to mitigate such problem ?

Do not hesitate if more information needed or further tests required.

 Regards,

[Shahbaz Youssefi]

Hello,

Thank you for the report. Could you please provide the contents of chrome://gpu?

[Damien Mfaransa]

Please find attached,

Regards.

[Damien Mfaransa]

Additional notes :

- happen the same with any recent build of chromium (~1 year from now), did not test with older releases

- same with any mesa vulkan driver release

- happens with both i915 and xe driver, did not test on AMD gpu

Again, severeness of freezes seems directly related to the amount of available CPU,

- on entry level 10th gen, effect is barely noticeable

- on Core Ultra 5, freeze can occur for several seconds

Any action throttling WebGL (chromium debug output, chrome tracing, JS profiler, ...) would mitigate the effect (or even no freezes at all)

[Shahbaz Youssefi]

Thanks. Some other things to try could be to use x11 instead of wayland, see if it makes a difference. Using a different GPU would also definitely be helpful. Unfortunately neither Vulkan nor DefaultANGLEVulkan are being looked at for Linux. With other changes planned for Chromium, some of the issues (and flags) here will be obsolete.

That said, I can reproduce some lag on RADV with the above combination of flags and the repro steps. It looks like after the rotation ends, maps starts loading more details and that is the cause of the lag (early on in rotation I can switch tabs quickly, but it "hangs" for a second around the time the rotation ends).

Could you please open an issue at crbug.com/new for further investigation? Please include the repro steps, chrome://gpu and the conversation here.