Arch Linux

paulp

Member

From: Italy

Registered: 2010-07-16

Posts: 5

Gnome Shell stutter

Hello everybody. I'm running Gnome Shell 3.24 on top of wayland with the nouveau (1.0.15-1) as 2D driver with mesa (17.0.5-1).
The problem I encounter is an incoherence in the 3D performance of the desktop.
I have two monitors, and my setup is this:
     - one 1920x1080 as main screen
     - one 1080x1920 (vertical) as secondary

My video card is:

 paull@mula ~ % lspci | grep VGA                                            
01:00.0 VGA compatible controller: NVIDIA Corporation GF119 [GeForce GT 610] (rev a1)

The problems I encounter are 2:
    - dragging a window is fluid on the vertical screen, but stutters on the horizontal one
    - when there is a maximized window on the vertical screen the desktop switching (that happens on the horizontal one) lags a lot

The presence of extensions doesn't seem to affect the problem.

Here are some more informations about my system:

paull@mula ~ % glxinfo | grep direct
direct rendering: Yes
    GL_ARB_depth_clamp, GL_ARB_derivative_control, GL_ARB_direct_state_access, 
    GL_ARB_draw_elements_base_vertex, GL_ARB_draw_indirect, 
    GL_ARB_half_float_vertex, GL_ARB_indirect_parameters, 
    GL_ARB_multi_draw_indirect, GL_ARB_occlusion_query2,

paull@mula ~ % glxinfo | grep OpenGL
OpenGL vendor string: nouveau
OpenGL renderer string: Gallium 0.4 on NVD9
OpenGL core profile version string: 4.3 (Core Profile) Mesa 17.0.5
OpenGL core profile shading language version string: 4.30
OpenGL core profile context flags: (none)
OpenGL core profile profile mask: core profile
OpenGL core profile extensions:
OpenGL version string: 3.0 Mesa 17.0.5
OpenGL shading language version string: 1.30
OpenGL context flags: (none)
OpenGL extensions:
OpenGL ES profile version string: OpenGL ES 3.1 Mesa 17.0.5
OpenGL ES profile shading language version string: OpenGL ES GLSL ES 3.10
OpenGL ES profile extensions:
 

paull@mula ~ % glxgears
Running synchronized to the vertical refresh.  The framerate should be
approximately the same as the monitor refresh rate.
341 frames in 5.0 seconds = 68.196 FPS
301 frames in 5.0 seconds = 59.996 FPS
301 frames in 5.0 seconds = 60.007 FPS

Is this a known issue?

Thank you in advance.

nchishol

Member

Registered: 2016-06-13

Posts: 6

Re: Gnome Shell stutter

I have been having potentially related troubles. Can you check if you are actually on a Wayland session?

echo $XDG_SESSION_TYPE

should spit back "wayland" or "x11".  For me, my gnome session reverts to x11 even though Wayland should be the default with nouveau + mesa on GNOME 3.24 (nvidia proprietary driver not installed).  I do notice very pronounced screen tearing (e.g. when moving around windows) with nouveau+mesa+x11 on my secondary monitor (both are horizontal). Although I wouldn't describe it as stuttering, so it could be a different issue. Switching to the proprietary nvidia driver + x11 resolves the issue for me. However, the screen tearing is also not present in a manually started nouveau+mesa+Wayland session.  This can be done by hitting ctrl+alt+f3 and running

XDG_SESSION_TYPE=wayland exec dbus-run-session gnome-session

(see the wiki page on GNOME)

The only thing that confuses me is why a Wayland GNOME session is not started by default when I am using the nouveau driver. I have the following in /etc/gdm/custom.conf,

[daemon]
...
# Uncoment the line below to force the login screen to use Xorg
#WaylandEnable=false
...

and I am selecting the regular GNOME option from the "gear-icon" drop down menu in GDM.

Edit: the nouveau driver seems to be resulting in a couple of boot errors on my machine, so maybe this has something to do with things (from journalctl -xb -p3):

May 03 15:04:15 DH3203-T1700-1 kernel: nouveau 0000:01:00.0: priv: HUB0: 00e584 811180ff (1a408216)
May 03 15:04:15 DH3203-T1700-1 kernel: nouveau 0000:01:00.0: bus: MMIO read of 00000000 FAULT at 3e6684 [ IBUS ]

I guess I'll stick to the proprietary drivers for now.

Also, note that I am using a different card

01:00.0 VGA compatible controller: NVIDIA Corporation GM107GL [Quadro K2200] (rev a2)
	Subsystem: NVIDIA Corporation Device 1097
	Kernel driver in use: nouveau

Last edited by nchishol (2017-05-03 19:18:45)

loqs

Member

Registered: 2014-03-06

Posts: 17,315

Re: Gnome Shell stutter

https://bugs.archlinux.org/task/53757?

paulp

Member

From: Italy

Registered: 2010-07-16

Posts: 5

Re: Gnome Shell stutter

I have been having potentially related troubles. Can you check if you are actually on a Wayland session?

echo $XDG_SESSION_TYPE

should spit back "wayland" or "x11".

It says "wayland", and as expected, since in my /etc/gdm/custom.conf i have this line:

[daemon]
...
# Uncoment the line below to force the login screen to use Xorg
WaylandEnable=True
...

...and since using "r" in the ALT+F2 launcher to reset the console returns "Restart is not available on Wayland".

Edit: the nouveau driver seems to be resulting in a couple of boot errors on my machine, so maybe this has something to do with things (from journalctl -xb -p3):

May 03 15:04:15 DH3203-T1700-1 kernel: nouveau 0000:01:00.0: priv: HUB0: 00e584 811180ff (1a408216)
May 03 15:04:15 DH3203-T1700-1 kernel: nouveau 0000:01:00.0: bus: MMIO read of 00000000 FAULT at 3e6684 [ IBUS ]

I don't have those lines in my journalctl -xd -p3, so I guess it's a different issue?

https://bugs.archlinux.org/task/53757?

I'm not sure the problem is the same: I don't have high CPU usage, and the stutter is present only when I have a window on my vertical screen.
I also tried to apply the patch present in this thread  (from the page you reported), but to no avail.

Ropid

Member

Registered: 2015-03-09

Posts: 1,069

Re: Gnome Shell stutter

You write you don't see high CPU usage. About that, how "bad" is this stutter you are seeing? Do you think the framerate is dropping really low while it appears to stutter, or do you think it could just be something going wrong with the synchronization to the display's vertical refresh? Something going wrong with vsync can be really noticeable compared to how animations look if everything works perfect.

Durden

Member

Registered: 2011-06-19

Posts: 261

Re: Gnome Shell stutter

Does the problem go away if you only use one monitor? I've seen similar problems with two monitors with different resolutions.

paulp

Member

From: Italy

Registered: 2010-07-16

Posts: 5

Re: Gnome Shell stutter

You write you don't see high CPU usage. About that, how "bad" is this stutter you are seeing? Do you think the framerate is dropping really low while it appears to stutter, or do you think it could just be something going wrong with the synchronization to the display's vertical refresh? Something going wrong with vsync can be really noticeable compared to how animations look if everything works perfect.

I don't really believe that the problem is caused by vsync. Just to be sure I tried playing a video with totem while moving around the window on the horizontal screen, and with a maximized window on the vertical one. The window's movement lags, but the video is being played smoothly.

edit: That was a bad explanation. I played a video on the horizontal screen while I had another window on the vertical one. Then I opened a third window on the horizontal screen and its movement lagged a lot.

Does the problem go away if you only use one monitor? I've seen similar problems with two monitors with different resolutions.

Yes, the problem does disappear when I use only one monitor.

Last edited by paulp (2017-05-05 12:34:25)