1824971 - Stuttery performance when connected to 2 different refresh rate displays

Status: RESOLVED WORKSFORME

(Core :: Graphics, defect, P2)

Description

[pasi123567]

User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:109.0) Gecko/20100101 Firefox/112.0

Steps to reproduce:

Many programs have difficulties synchronizing different refresh rates across multiple monitors. Firefox is no exemption here, but since this is handled way better in chromium based browsers and there is a workaround, this should be able to be improved.

To make this issue easily visible, open the following website
https://www.testufo.com/animation-time-graph

This graph shows the smoothness of the browsers performance but the results will not show the actual problem here and are NOT important. Wait until the performance is steady and then look closely at the movement of this graph. As the graph moves, the green bar will start to flicker if performance is suboptimal. Using a 144hz and a 270hz monitor there will be very obvious flicker. This is not the case in chromium based browsers.

A workaround to stop the flickering and therefore the microstutters is to set both displays to the same refresh rate, after that restart Firefox and then the flicker will be gone. Now even after changing the refresh rates back to different ones, as long as Firefox wont be closed, the stuttering will still be fixed and not noticeable.

Actual results:

When browsing the web, especially when scrolling, stuttery movements are noticeable.

Expected results:

Movements should be smooth, even when 2 monitors are connected with different refresh rates.

Comment 1

[BugBot [:suhaib / :marco/ :calixte]]

The Bugbug bot thinks this bug should belong to the 'Core::Performance' component, and is moving the bug to that component. Please correct in case you think the bot is wrong.

Comment 2

[BugBot [:suhaib / :marco/ :calixte]]

This bug was moved into the Performance component.

:pasi123567, could you make sure the following information is on this bug?

• For slowness or high CPU usage, capture a profile with http://profiler.firefox.com/, upload it and share the link here.
• For memory usage issues, capture a memory dump from about:memory and attach it to this bug.
• Troubleshooting information: Go to about:support, click "Copy raw data to clipboard", paste it into a file, save it, and attach the file here.

If the requested information is already in the bug, please confirm it is recent.

Thank you.

Comment 3

[BugBot [:suhaib / :marco/ :calixte]]

This bug was moved into the Performance component.

:pasi123567, could you make sure the following information is on this bug?

• For slowness or high CPU usage, capture a profile with http://profiler.firefox.com/, upload it and share the link here.
• For memory usage issues, capture a memory dump from about:memory and attach it to this bug.
• Troubleshooting information: Go to about:support, click "Copy raw data to clipboard", paste it into a file, save it, and attach the file here.

If the requested information is already in the bug, please confirm it is recent.

Thank you.

Comment 4

[pasi123567]

FF Profile stutter: https://share.firefox.dev/3G5Vmvp
FF Profile workaround (no stutter): https://share.firefox.dev/3lRbpq3

about:support data stutter: https://pastebin.com/nGgLPnAx
about:support data workaround: https://pastebin.com/BrwNUFD4

Comment 5

[BugBot [:suhaib / :marco/ :calixte]]

This bug was moved into the Performance component.

:pasi123567, could you make sure the following information is on this bug?

• ✅ For slowness or high CPU usage, capture a profile with http://profiler.firefox.com/, upload it and share the link here.
• For memory usage issues, capture a memory dump from about:memory and attach it to this bug.
• Troubleshooting information: Go to about:support, click "Copy raw data to clipboard", paste it into a file, save it, and attach the file here.

If the requested information is already in the bug, please confirm it is recent.

Thank you.

Comment 6

[pasi123567]

Attachment: memory-report stutter.json.gz

Comment 7

[pasi123567]

Attachment: memory-report workaround.json.gz

Comment 8

[pasi123567]

Attachment: aboutsupport data stutter.txt

Comment 9

[pasi123567]

Attachment: aboutsupport data workaround.txt

Comment 10

[pasi123567]

Still hoping for a response. I feel like this is an easy issue to fix to make Firefox much more smooth for multiple display setups.

Comment 11

[Bas Schouten (:bas.schouten)]

This is a graphics issue, moving to the appropriate component.

Comment 12

[BugBot [:suhaib / :marco/ :calixte]]

The severity field is not set for this bug.
:bhood, could you have a look please?

For more information, please visit BugBot documentation.

Comment 13

[pasi123567]

Hello, I just wanted to put an update on here. I think this may have been fixed on the GPU driver side. It seems that on nvidia at least, the display set as the primary used display will always be used as reference to what monitor will be prioritized in synching.
In my experience it seems that now the browser will always run smooth on my main display which is the one I use firefox on. The second display on the other hand will always not feel smooth but this is the same on chrome now too so I would say that this is issue is resolved.

The only thing I wonder now is if this is a windows side or nvidia fix and how it would look on the amd side of things but since I don't have any amd GPU I wouldn't be able to test this.

Comment 14

[Ashley Hale [:ahale]]

More recently there have been Windows updates from 2024-05-29 (Windows 11 22H2 or later) and 2024-06-25 (Windows 10 22H2) that say they fix flickering issues with video playback or compositor surfaces that may be the underlying cause; they match my mental model of this issue very closely, and I think both refer to the same fix.

Quoting a Windows 11 update https://support.microsoft.com/en-us/topic/may-29-2024-kb5037853-os-builds-22621-3672-and-22631-3672-preview-dcf14fd8-84d6-4234-9d5b-784c319cd7cf :

• This update addresses an issue that distorts parts of the screen. This occurs when you use a Chromium-based browser to play a video.

Quoting a Windows 10 update https://support.microsoft.com/en-us/topic/june-25-2024-kb5039299-os-build-19045-4598-preview-d4e3e815-fdd8-465e-8144-42afa165efed :

• This update addresses an issue that affects Direct Composition batched presentations. A brief flash of triangles or boxes show on the screen. This issue affects browsers, like Microsoft Edge, and other apps.

Comment 15

[pasi123567]

Alight, since this seems to be fixed then I'll close the issue :)