

That machine has a faster hard drive, so maybe it is better able to feed the CPU's. For that box, Handbrake typically pegs all 6 cores at 100% almost continually during the run.

I have an overclocked i7-8700K with 6 cores. Whether 6 cores is the optimum remains to be seen. You would definitely be better served to limit the number of cores that handbrake uses. That is about a 60% increase in CPU utilization, which I think would translate into a 60% increase in compute power for each instance. The total CPU utilization for the three instance, 6 core each was averaging 61%. The other CPU just had 6 cores for the third instance running in that same 85-100% range. One CPU then had all cores running 85 to 100%.

I then limited each of the three instances to 6 cores each, with no over lapping cores. The total CPU utilization was averaging 38%. I then started 3 instances of Handbrake, and let them all use all cores. All 6 active cores were running between 85 and 100%. When I limited the affinity to just 6 cores, the CPU utilization went up from 7 to 11 percent. A single instance of Handbrake seemed to be trying to use all 24 cores. I was converting several 12 GB files using X265 10bit in Handbrake Ver 1.1.0. I have a dual Xeon 6146, with 12 cores each.
