[cfn]

That is an interesting idea. Can you tell me what is the switch for number of cores?

[washadjeffmad]

-t 32

Use a maximum of the number of physical cores and then scale down.

[cfn]

Thanks, -t 32 (instead of -t 13 which is what comes as default) makes a big difference in CPU usage across all cores. Not quite 100% but all cores are above 50% with many at 100%. It speeds up just a tiny bit the eval t/s to 3.3 (from 2.9).