1096904 - Screen tearing and jank when smooth scrolling

Status: RESOLVED WORKSFORME

(Core :: Graphics, defect)

Description

[Jakub Okoński]

Attachment: Data from the Performance section from Dev tools when scrolling

User Agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/38.0.2125.111 Safari/537.36

Steps to reproduce:

Open up any site (I used webmaker.org, it has a static, simple layout), then scroll with smooth scrolling enabled, or by dragging the scrollbar smoothly.


Actual results:

I'm not an expert on this vocabulary, but it definitely isn't vsynced properly. When scrolling down, buttons on the site seem to be jumping up&down just slightly. Also seeing screen tearing in some places.


Expected results:

Smooth scrolling should perform as on Windows, where I can't notice any such issues.

Comment 1

[Jakub Okoński]

Worth noting, I'm using ArchLinux with xf86-video-ati driver and it all got better with `Option "SwapbuffersWait" "True"`, but it's still not as smooth as on Windows.

Comment 2

[Jakub Okoński]

User agent is meaningless since I reported this from Chrome, the actual software on which I experienced this was Firefox Aurora/Developer - 35.0a2.

Comment 3

[Loic]

Do you observe this behavior with 33.1?

Comment 4

[Jakub Okoński]

Yes, it's the same on 33.0.2

Comment 5

[Jakub Okoński]

33.1 aswell, yes.

Comment 6

[Jakub Okoński]

Actually, I looked on Windows again and it's the exact same tearing as with enabling SwapbuffersWait on Linux.

Comment 7

[ivan]

I see this all the time in Firefox 42 on Ubuntu 15.10 with the nvidia-355 drivers, and it does not seem curable by flipping gfx/vsync/offmainthread options in about:config.

Comment 8

[ivan]

I don't have any screen tearing issues in Firefox when running Compton with this configuration: http://ubuntuforums.org/showthread.php?t=2144468

Note that the XFCE4 compositor (in XFCE 4.12 at least) introduces additional screen tearing and should be disabled.  (At least with nvidia-355/358).

Chrome does not seem to require a compositor to avoid tearing.

Comment 9

[Liviu Cirdei]

User Agent 	Mozilla/5.0 (X11; Linux x86_64; rv:46.0) Gecko/20100101 Firefox/46.0
Build ID 	20160105030211

@Reporter, 

Are you still experiencing the issue on latest Firefox versions (Firefox 43/Nightly 46)? I tried on Nightly 46 but I didn't manage to reproduce this issue. If you still can reproduce it, could you provide a recorded video with the issue. That would help.

Thank you.

Comment 10

[Jakub Okoński]

I just checked and yes it still happens on 43.0.1. Tried capturing it on video but you can only see jank/frame skips on it, not the tearing. Would seeing the skips be valuable to you?

I can provide my hardware setup, Xorg settings, just tell me what you need.

Comment 11

[ivan]

I still see this with Firefox 43 and 46 on Ubuntu 15.10, nvidia-352 drivers, no X compositor.  As far as I can tell, Firefox is not able to avoid tearing on Linux when there is no compositor.

I don't know how Firefox's internal compositing works, but the way the tearline slowly drifts across the screen suggests that Firefox is compositing at a hz very close to my monitor, but doesn't have any way to "sync to vblank".

Comment 12

[Liviu Cirdei]

I changed the component to Core:Graphics so people with more experience on this matter to be involved.

Comment 13

[Stefano]

- Firefox 49
- Ubuntu 14.04 with KDE 4.13
- Fedora 24 with Gnome 3.20 with X and with Wayland

I have tearing while scrolling and it doesn't matter, if hardware acceleration is enabled or not.

I have NO problems with Chrome, so I might consider to switch to Chrome!

Sadly this bug survived so long!

Comment 14

[Stefano]

To add: Without hardware acceleration tearing is less frequently, but it still happens.

Comment 15

[Milan Sreckovic [:milan] (needinfo for best results)]

My version of tearing is with Nvidia on the same machine where it works fine with Intel graphics.  And it got a bit worse with a more recent Nvidia driver, that had some fixes for g-sync.

Comment 16

[Jakub Okoński]

I don't experience it anymore. I guess the graphics stack improved a lot in the past couple of years :D

The smooth scrolling experience is not stutter-free, but it's always some reflow or JS execution that causes stutter, nothing inherent to Firefox. Static pages such as bugzilla scroll well, tear-free and close to 144fps these days.

OK to close this issue on my end.