Compton backend config optimization

What I always used for my configuration through copy-paste from various sources is presented next but the only changes I made to it was when it crashed. Now that I have amdgpu finally working with all of the associated bling, I decided to review the performance situation.

Final file available here

Resources used:

Performance considerations by chjj found here
$man 1 compton

Original Config

backend = "glx";
glx-no-stencil = true;
glx-copy-from-front = false;
glx-swap-method = 2;
refresh-rate = 0;
vsync = "opengl";
dbe = false;
paint-on-overlay = true;
sw-opti = false;
unredir-if-possible = true;

Turn it on and off again

During these benchmarks I kept normal activity on the screen and an 1080p 8 hour youtube video of a fireplace on 1/4 of the screen. This firefox window was also supposed to be used for the partial update benchmark but --benchmark-wid simply refused everything I threw at it so I decided to postpone such test to a later date.

The benchmark used will be the following to simulate full screen repaint. vblank_mode is set to 0 to disable AMDGPU's default vsync.

seq 5 | xargs -P1 -Iz /usr/bin/time -f "%e" compton --config ~/.compton.conf --benchmark 5000

First thing I did was to remove all backend options except the backend glx to get a baseline then add vsync to check if it impacted performance.

Config 2 - swap method 2

backend = "glx";
vsync="opengl-mswc"
glx-no-stencil = true;
glx-swap-method = 2;
unredir-if-possible = true;
glx-use-gpushader4 = true;

Config 3 - swap method 2 && no-rebind-pixmap

backend = "glx";
vsync="opengl-mswc"
glx-swap-method = 2;
glx-no-stencil = true;
glx-use-gpushader4 = true;
glx-no-rebind-pixmap = true;
unredir-if-possible = true;

Config 4 - swap method 6

backend = "glx";
vsync="opengl-mswc"
glx-swap-method = 6;
glx-no-stencil = true;
glx-use-gpushader4 = true;
unredir-if-possible = true;

Data

	Original	GLX	Vsync-mswc	Config 2	Config 3	Config 4
1	83.45	12.24	12.68	9.59	10.44	10.02
2	83.42	12.4	12.57	9.09	9.93	10.08
3	83.38	12.22	12.66	9.97	9.87	10.28
4	83.14	11.93	12.09	9.07	9.76	10.3
5	83.54	11.18	12.08	8.29	9.67	9.89
Average	83.386	11.994	12.416	9.202	9.934	10.114

Time in seconds to repaint the screen 5000 times plotted

Conclusions

Adding vsync didn't change the results of the benchmark.
Disabling gpushader4 didn't make much difference, or at least, within the margin error.
no-rebind-pixmap appears to reduce performance but since it's most useful in a specific situation it's still an option to consider.
I'm keeping config 2 for now.