action #139103

Updated by okurz 6 months ago

## Motivation 
 Currently on OSD there is a longer job queue in particular for ppc64le for multiple reasons, see #139010. One idea to decrease number of x86_64 worker slots on osd to give ppc64le jobs a better chance to be assigned jobs due to the OSD openQA instance job limit. 

 ## Acceptance criteria 
 * **AC1:** The impact of worker instance ratio by arch/class has been verified 
 * **AC2:** Given the openQA instance job limit is impacting the ppc64le job queue When the ratio of ppc64le/all workers has been increased Then the ppc64le job age is lower 

 ## Suggestions 
 * Look up current number of x86_64 and qemu ppc64le jobs assuming that we have a very low ppc64le/all ratio, e.g. many workers for qemu_x86_64 and very few for qemu_ppc64le (16 as of 2023-11-04). 
 * Reduce number of x86_64 qemu slots if we have "too many" 
 * Monitor for the impact on qemu_ppc64le job age 

 ## Rollback steps 
 * Re-enable openQA OSD workers w35-w36, remove according alert