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Hi,

I'd like to propose (and implement) a feature for Liberty that would allow 
configuration of the pinning of the emulator when CPU pinning is enabled. 
(Currently the emulator is affined to the logical OR of all pCPUs used by the 
instance.)

The general idea is to add an optional flavor extra spec (or image metadata):

"hw:emulatorpin=<vcpulist>"

If specified, this would affine the emulator to the pCPUs corresponding to the 
specified vCPUs.  If not specified, the emulator would be affined as it is 
currently.

The rationale for this is that for pure userspace tasks we may want to give 
certain vCPUs as much CPU time as possible.  If the emulator is allowed to run 
run on the corresponding pCPU, then that robs the vCPU of some time--reducing 
throughput and increasing latency.

Would something like this be eligible for the "trivial blueprint" process?

Thanks,
Chris