Linux - rendering performance after switching from nvidia to nouveau drivers

Question

I use UBuntu 14.04 LTS. I have purged all nvidia proprietary drivers and currently my system use Nouveau driver. Here is an output from glxinfo | grep OpenGL :

when using nvidia propietary drivers

OpenGL vendor string: NVIDIA Corporation
OpenGL renderer string: GeForce GTX 970/PCIe/SSE2
OpenGL core profile version string: 4.3.0 NVIDIA 346.59
OpenGL core profile shading language version string: 4.30 NVIDIA via Cg compiler
OpenGL core profile context flags: (none)
OpenGL core profile profile mask: core profile
OpenGL core profile extensions:
OpenGL version string: 4.5.0 NVIDIA 346.59
OpenGL shading language version string: 4.50 NVIDIA
OpenGL context flags: (none)
OpenGL profile mask: (none)
OpenGL extensions:

when using nouveau driver

OpenGL vendor string: VMware, Inc.
OpenGL renderer string: Gallium 0.4 on llvmpipe (LLVM 3.6, 256 bits)
OpenGL version string: 3.0 Mesa 10.6.0-devel
OpenGL shading language version string: 1.30
OpenGL context flags: (none)
OpenGL extensions:

When I run a gpu benchmark triangle test I get following results:

• nvidia driver: 304455 points, 5073fps

• nouveau driver: 8466 points, 142 fps

There is a massive drop in performance. Can I change something in nouveau settings to get better results ?

Edit1

glxinfo |egrep -w 'rendering|renderer' :

• direct rendering: Yes
• OpenGL renderer string: Gallium 0.4 on llvmpipe (LLVM 3.6, 256 bits)

I don't use the system in Virtual Machine.

Answer 1

Did you check if 3d is enabled?

glxinfo |egrep  -w 'rendering|renderer'

If you read something about "raster" or "no",then is not enabled. Even if enabled the opensource driver are good,but there is a lot of work to do to reach at least for old cards the same performance of the nvidia proprietary driver.

Is not clear this

"OpenGL vendor string: VMware, Inc." Using this in a vm?

Answer 2

You'll have to look into your /var/log/Xorg.*.log file (where * means the first number in your $DISPLAY environment variable) to find out why 3D acceleration hasn't been enabled. Gallium 0.4 on llvmpipe is a software renderer, so this indicates that nouveau is not really in use. You can also try the following command to check for warnings about misconfiguration of libGL:

LIBGL_DEBUG=verbose glxinfo > /dev/null

This will redirect all the normal output of glxinfo to /dev/null (the "hole" device) while retaining all the warnings on the console.

Answer 3

I've encountered same issue, but under different circumstances. Only available renderer was llvm.

After lot of googling I realised, because of different bug, I put nomodeset into grub (/etc/default/grub) in the line GRUB_CMDLINE_LINUX_DEFAULT

In my setup the machine works without this parameter just fine.

Check, if there is parameter nomodeset in grub and remove it. Try if it helps.