Is it possible to set a more generic process affinity (automatically)?

Question

I know with start /affinity X where X is a hex-number bit-masking the CPUs to be used a process can be started to use certain CPUs only. However, is there a possibility to state something like "start this process using 50% of the available cores, pick them on your own, but don't use CPU3"?

Answer 1

That functionality is not exposed via command-line (nor Windows API supports it directly).

It should be relatively straight forward to implement is in specific code but that would most definitely require custom program. I am not aware that there is program supporting such rich functionality.