Messages in this thread | | | Date | Tue, 1 Aug 2017 09:57:28 +0200 | From | Peter Zijlstra <> | Subject | Re: [PATCH 3/3] mm/sched: memdelay: memory health interface for systems and workloads |
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On Mon, Jul 31, 2017 at 02:41:42PM -0400, Johannes Weiner wrote: > On Mon, Jul 31, 2017 at 10:31:11AM +0200, Peter Zijlstra wrote:
> > So could you start by describing what actual statistics we need? Because > > as is the scheduler already does a gazillion stats and why can't re > > repurpose some of those? > > If that's possible, that would be great of course. > > We want to be able to tell how many tasks in a domain (the system or a > memory cgroup) are inside a memdelay section as opposed to how many
And you haven't even defined wth a memdelay section is yet..
> are in a "productive" state such as runnable or iowait. Then derive > from that whether the domain as a whole is unproductive (all non-idle > tasks memdelayed), or partially unproductive (some delayed, but CPUs > are productive or there are iowait tasks). Then derive the percentages > of walltime the domain spends partially or fully unproductive. > > For that we need per-domain counters for > > 1) nr of tasks in memdelay sections > 2) nr of iowait or runnable/queued tasks that are NOT inside > memdelay sections
And I still have no clue..
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