Messages in this thread | | | From | "Liang, Kan" <> | Subject | RE: [PATCH V2 1/1] perf/x86: Add Intel power cstate PMUs support | Date | Fri, 28 Aug 2015 15:00:47 +0000 |
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> On Tue, Aug 25, 2015 at 1:15 PM, Liang, Kan <kan.liang@intel.com> wrote: > > > >> >> > > >> >> I understand that these metrics are useful and needed however if I > >> >> look at the broader picture I see many PMUs doing similar things > >> >> or appearing different when they are actually very close. It would > >> >> be nice to have a more unified approach. You have RAPL (client, > >> >> server) which appears as the power PMU. You have the PCU uncore > on > >> >> servers which also provides C-state residency info. Yet, all these > >> >> appear differently and expose events with different names. > >> >> I think we could benefit from a more unifie approach here such > >> >> that you would be able to do > >> >> > >> >> $ perf stat -a -e power/c6-residency/, power/energy-pkg/ > >> >> > >> >> on client and server without having to change the pmu name of the > >> >> event names. > >> > > >> > Yes, I agree. I'll think about it. > >> > > > > > Hi Stephane, > > > > I thought more about your suggestion regarding to create a unified > > power PMU for all related events include RAPL and residency. > > It looks we can benefit from a simple unified name, but it also brings > > too much confusion. > > - cstate residency is the time of the core/socket in specific cstate. > > While RAPL event is the power core/socket which consumed. > > They have different concepts. > > - cstate residency includes both per-core and per-socket events. > > RAPL events is only per-socket. So the CPU mask is different. > > It's very confused that the events in same PMU has different CPU > mask. > > > > So I think it should be better to use different PMUs for RAPL and > residency. > > > > What do you think? > > > Well, you are maybe confusing events with PMU. If you look at the core > PMU, it cover many events measuring vastly different aspects of the core. > Some events are per-thread, others are per-core. > > Here, I was thinking it would be good to have some power// PMU with > many events covering cstate residency, energy consumption. And yes, > some events would be per-socket, others per-core.
So you agree to create two new cstate PMUs (per-core and per-socket) to cover cstate residency? If so, I will start to implement the V3 version for two new PMUs.
Thanks, Kan
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