Wondering if a user-space gettimofday() for kvm-clock has been considered before. I am seeing a pretty large difference in performance between tsc and kvm-clock. I have to assume at least some of this is due to the mode switch for kvm-clock. Here are the results:

(this is a 16 vCPU VM on a 16 thread 2S Nehalem-EP host, looped gettimeofday() calls on all vCPUs)

tsc:            .0645 usec per call
kvm-clock:      .4222 usec per call (6.54x)


-Andrew Theurer

--
To unsubscribe from this list: send the line "unsubscribe kvm" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to