Open Bug 1667165 Opened 2 months ago Updated 2 months ago

Slow scrolling with two or more windows open

Categories

(Core :: Graphics: WebRender, defect)

Firefox 81
x86_64
Linux
defect

Tracking

()

Tracking Status
firefox81 --- disabled
firefox82 --- disabled
firefox83 --- disabled

People

(Reporter: lucaswilm, Unassigned)

References

(Blocks 1 open bug)

Details

(Keywords: perf)

Attachments

(1 file)

User Agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:81.0) Gecko/20100101 Firefox/81.0

Steps to reproduce:

I opened a window and went to https://news.google.com (for example). So I opened another window on any random website.

Actual results:

Firefox scrolling was slow in both open windows. However, with only one window open, scrolling is normal. Or when one window is minimized and the other is open, scrolling is also normal.

Expected results:

Scrolling should be fluid regardless of the number of windows open.

Component: Untriaged → General
OS: Unspecified → Linux
Hardware: Unspecified → x86_64
Component: General → Panning and Zooming
Product: Firefox → Core

Thanks for the report. Could you please provide the following information:

  1. How many monitors you have, and their resolutions (and if any of them are HiDPI).
  2. The contents of about:support.
  3. If possible, a performance profile during a slow scroll (just a few seconds) taken using profiler.firefox.com?

Thanks!

Attached file about:support contents
(In reply to Botond Ballo [:botond] from comment #1)
> Thanks for the report. Could you please provide the following information:
> 
>   1. How many monitors you have, and their resolutions (and if any of them are HiDPI).
>   2. The contents of `about:support`.
>   3. If possible, a performance profile during a slow scroll (just a few seconds) taken using [profiler.firefox.com](https://profiler.firefox.com/)?
> 
> Thanks!

Thanks for the answer! I will try to give all of this information correctly.

1. I have only 1 monitor, model Flatron E2260 with resolution 1920x1080 and 60,0 Hz.
2.

(In reply to Botond Ballo [:botond] from comment #1)

Thanks for the report. Could you please provide the following information:

  1. How many monitors you have, and their resolutions (and if any of them are HiDPI).
  2. The contents of about:support.
  3. If possible, a performance profile during a slow scroll (just a few seconds) taken using profiler.firefox.com?

Thanks!

Thanks for the answer! I will try to give all of this information correctly.

  1. I have only 1 monitor, model Flatron E2260 with resolution 1920x1080 and 60,0 Hz.
  2. Guess I attached it somewhere?
  3. https://share.firefox.dev/3kPlq0u (first I opened a website in a window and scrolled the page. Then I opened another window on another website and scrolled the page in both)

I'm sorry for the inconvenience, I think I sent two responses. The first incomplete, with the about: support attached and the other with the continuation. I fumbled.

Thanks! Could I ask you to try something, and let me know if it improves the performance?

  1. Go to about:config. Click past the warning if necessary.
  2. Type gfx.webrender.force-disabled into the search box.
  3. Toggle the pref to "true".
  4. Restart Firefox.
Attachment #9177979 - Attachment description: Informações básicas sobre o aplicativo -------------------------------------- Nome: Firefox Versão: 81.0 ID da compilação: 20200917005511 ID da distribuição: canonical User Agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:81.0) Gecko/20100101 Fi → about:support contents

(In reply to Botond Ballo [:botond] from comment #5)

Thanks! Could I ask you to try something, and let me know if it improves the performance?

  1. Go to about:config. Click past the warning if necessary.
  2. Type gfx.webrender.force-disabled into the search box.
  3. Toggle the pref to "true".
  4. Restart Firefox.

It does not improve performance. If I disable WebRender, scrolling is bad in any scenario, even with a single window open.

Thanks! One more question: if you open about:support with WebRender disabled, and look for "Compositing" ("Composição"), does it say "OpenGL" or "Basic"?

It say "Basic" when WebRender is disabled.

Something curious:

My operating system is Linux and the distribution is Xubuntu. That is, I am using the Xfce desktop environment and it has virtual desktops, usually I use 4, as it comes in the standard.

If I move the second window to another virtual desktop, scrolling is nice and smooth across all windows while they are in different virtual desktops.

Jeff, are there any known issues with multiple WR windows being visible on Linux+NVidia? It sounds like if both windows are visible scrolling is bad, but if one window is minimized or moved to a different virtual desktop then things are good again. This feels more like a WR bug than an APZ bug.

Flags: needinfo?(jmuizelaar)

I've not heard of anything, but Andrew and Nical have been watching Linux closer than me.

Flags: needinfo?(nical.bugzilla)
Flags: needinfo?(jmuizelaar)
Flags: needinfo?(aosmond)

We know that alternativng between multiple GL context presenting is very slow with nvidia proprietary drivers on Linux, we don't know why. I can easily reproduce the issue, for example by having a video play with picture-in-picture and scrolling a page at the same time.

Blocks: wr-linux
Flags: needinfo?(nical.bugzilla)
Blocks: wr-nv-linux
No longer blocks: wr-linux
Status: UNCONFIRMED → NEW
Component: Panning and Zooming → Graphics: WebRender
Ever confirmed: true
Keywords: perf
See Also: → 1659848, 1497481
Severity: -- → S3
Flags: needinfo?(aosmond)
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