Re: [PATCH 0/3]measure SMI cost

[Andi Kleen]

> > A new --smi-cost mode in perf stat is implemented to measure the SMI cost
> > by calculating cycles and aperf results. In practice, the percentages of
> > SMI cycles should be more useful than absolute value.
> 
> That's only true for performance oriented analysis, but for analyzing the
> root cause of latencies the actual cycles are definitely interesting.

perf stat also prints the absolute cycles of course (unless you do --metric-only)

It cannot print individual cycles (per SMI occurrence), the only
way to do that would be to poll constantly.

-Andi