On Mon, Jul 08, 2019 at 07:00:08PM -0700, Ankur Arora wrote: > On 2019-06-26 12:23 p.m., Thomas Gleixner wrote: > > On Wed, 26 Jun 2019, Raslan, KarimAllah wrote: > > > On Wed, 2019-06-26 at 10:54 -0400, Konrad Rzeszutek Wilk wrote: > > > > There were some ideas that Ankur (CC-ed) mentioned to me of using the perf > > > > counters (in the host) to sample the guest and construct a better > > > > accounting idea of what the guest does. That way the dashboard > > > > from the host would not show 100% CPU utilization. > > > > > > You can either use the UNHALTED cycles perf-counter or you can use MPERF/APERF > > > MSRs for that. (sorry I got distracted and forgot to send the patch) > > > > Sure, but then you conflict with the other people who fight tooth and nail > > over every single performance counter. > How about using Intel PT PwrEvt extensions? This should allow us to > precisely track idle residency via just MWAIT and TSC packets. Should > be pretty cheap too. It's post Cascade Lake though. That would fully claim PT just for this stupid accounting thing and be completely Intel specific. Just stop this madness already.
