Re: [Powertop] Query: Weird Output values: Percentage over 100%
Sergey Senozhatsky <sergey.senozhatsky at gmail.com> Tue, 04 Sep 2012 15:37:45 +0300
| Newsgroups | dev.linux.lists.powertop |
|---|---|
| Message-ID | <20120904123745.GA2993@swordfish> |
On (09/04/12 11:30), Igor Zhbanov wrote:
> Arjan van de Ven wrote:
>
> >shouldn't... the buffers are quite large....
>
> By the way, I just curious, why events processing are limited to 5000?
> I mean the PowerTOP has f half-megabyte buffer for each type of events
> but wishes to process only 5000 even if data is there?
>
> void perf_event::process(void *cookie)
> {
> ...
> while (pc->data_tail != pc->data_head && i++ < 5000) {
> ...
>
> In the case of many cores sched:switch will be fired at least CONFIG_HZ * nr_cpus
> times per second (as I understand), and that could easily be larger than 5000.
> Especially when we measuring for several seconds.
>
good spot.
Also interested if we will fit all perf samples on (e.g.) loaded 64 core system.
-ss