Re: [RFC] psi: Add additional PSI counters for each type of memory pressure

[Suren Baghdasaryan <surenb@google.com>]

On Wed, Nov 10, 2021 at 8:46 AM Georgi Djakov <djakov@kernel.org> wrote:
>
>
> On 10.11.21 18:14, Peter Zijlstra wrote:
> > On Wed, Nov 10, 2021 at 07:36:37AM -0800, Georgi Djakov wrote:
> >> @@ -21,7 +19,18 @@ enum psi_task_count {
> >>       * don't have to special case any state tracking for it.
> >>       */
> >>      NR_ONCPU,
> >> -    NR_PSI_TASK_COUNTS = 4,
> >> +    NR_BLK_CGROUP_THROTTLE,
> >> +    NR_BIO,
> >> +    NR_COMPACTION,
> >> +    NR_THRASHING,
> >> +    NR_CGROUP_RECLAIM_HIGH,
> >> +    NR_CGROUP_RECLAIM_HIGH_SLEEP,
> >> +    NR_CGROUP_TRY_CHARGE,
> >> +    NR_DIRECT_COMPACTION,
> >> +    NR_DIRECT_RECLAIM,
> >> +    NR_READ_SWAPPAGE,
> >> +    NR_KSWAPD,
> >> +    NR_PSI_TASK_COUNTS = 16,
> >>   };
> >>
> >
> >> @@ -51,9 +80,20 @@ enum psi_states {
> >>      PSI_MEM_FULL,
> >>      PSI_CPU_SOME,
> >>      PSI_CPU_FULL,
> >> +    PSI_BLK_CGROUP_THROTTLE,
> >> +    PSI_BIO,
> >> +    PSI_COMPACTION,
> >> +    PSI_THRASHING,
> >> +    PSI_CGROUP_RECLAIM_HIGH,
> >> +    PSI_CGROUP_RECLAIM_HIGH_SLEEP,
> >> +    PSI_CGROUP_TRY_CHARGE,
> >> +    PSI_DIRECT_COMPACTION,
> >> +    PSI_DIRECT_RECLAIM,
> >> +    PSI_READ_SWAPPAGE,
> >> +    PSI_KSWAPD,
> >>      /* Only per-CPU, to weigh the CPU in the global average: */
> >>      PSI_NONIDLE,
> >> -    NR_PSI_STATES = 7,
> >> +    NR_PSI_STATES = 18,
> >>   };
> >
> > Have you considered what this does to psi_group_cpu's size and layout
> > and the impact thereof on performance?
>
> Thanks, i will definitely add some numbers in case there are no other
> major arguments against this RFC patch.

Please CC me too in the future postings.
Thanks,
Suren.

>
> BR,
> Georgi
>