On 06/23/2016 12:12 PM, Thomas Gleixner wrote:
On Thu, 23 Jun 2016, Daniel Lezcano wrote:
On 06/23/2016 10:41 AM, Thomas Gleixner wrote:
Is it really required to do this per interrupt rather than providing per cpu
statistics of interrupts which arrived in the last X seconds or whatever
timeframe is relevant for this.
Perhaps I am misunderstanding but if the statistics are done per cpu without
tracking per irq timings, it is not possible to extract a repeating pattern
for each irq and have an accurate prediction.
I don't see why you need a repeating pattern for each irq. All you want to
know is whether there are repeating patterns of interrupts on a particular
cpu.
struct per_cpu_stat {
u32 irq;
u64 ts;
};
storing 32 entries of the above should give you enough information about
patterns etc. If you have a high rate of interrupts on that cpu it does not
matter at all whether thats from one or several devices. If you have only a
few then this storage is sufficient to get the desired information.
Mmmh, yes. I will investigate this patchset by replacing the percpu
irqdesc's timings field by a per cpu irq event timings array.
Thanks !
-- Daniel
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