Destop environment and gl performance...

Can someone explain why the destop environment (here Cinnamon) can have
such an impact on the graphic card performance ?

Using glmark, we see a 2x to 20x factor in glmark performance between
various destops (mate,xlfce,cinnamon). What can justify such a huge gap
in perfs ?

Even better is there a way to investigate the GPU usage (a la ps or top)
to understand such issues ?

Thank's in advance..



Re: Destop environment and gl performance...

By Adam Jackson at 05/29/2019 - 14:53

On Wed, 2019-05-29 at 19:45 +0200, Theodore Papadopoulo wrote:
Because (I suspect) you're not measuring glmark2 --off-screen, which
means the output that glmark generates has to also be presented to the
screen, which - for cinnamon, and gnome-shell, and kwin's gl mode -
means that display _also_ uses GL and so will be contending with glmark
for the GPU.

The offscreen glmark numbers ought to be nearly identical.

GL profiling is something of a dark art with the open source tools. If
you have an intel gpu you could start with intel_gpu_top from the igt-
gpu-tools package.

- ajax