Recommended settings for AMD Radeon RX 7900 XTX

Samuel,

My experience with AMD gpus under Ubuntu is dated.  But the guidelines seem to be the same as for NVIDIA gpus.

Usually this is a matter of testing.  First you run enough 1 task per GPU to get a baseline.

Then you use the app_config.XML file to switch to two per GPU.

<app_config>
<app>
<name>hsgamma_FGRPB1G</name>
<gpu_versions>
<gpu_usage>0.5</gpu_usage>
<cpu_usage>1.0</cpu_usage>
</gpu_versions>
</app>
<app>
<name>einsteinbinary_BRP7</name>
<gpu_versions>
<gpu_usage>0.5</gpu_usage>
<cpu_usage>0.9</cpu_usage>
</gpu_versions>
</app>
</app_config>

If the time each of those 2x tasks is LESS than twice the time the 1x task took to process you have a winner.

To confirm if 3x you use the same rule of thumb except your baseline is the 1x number you get from dividing the 2x time by 2.

If the time (by calculation) comes in with a 1x calculated time that is below the calculated time of the previous one (2x wall clock time divided by 2) then 3x is still gaining you faster total processing.

If your GPU is showing nearly 100% utilization all the time, usually you are going to not gain anything from trying the next increase in running multiple tasks on your GPU.

If your GPU is running 80% utilization usually you can get more total production by adding another GPU task.

Generally running 1 CPU thread per GPU task is a safe guess.  You usually need between 2-4 threads not committed to anything (setting to something like 86.75% for a 8c/16t CPU).  If your CPU shows processing load above 95% all the time you may have an over committed CPU which will slow everything down.

If your system shows instability (computation errors) in processing GPU tasks often an older version of the GPU driver will get rid of that problem.

HTH,

Tom M