On Fri, Aug 07, 2009 at 07:38:34AM +1000, Ken McDonell wrote:
>
> So, if you have 2 CPUs and are sampling once per second, expect the
> counter kernel.all.cpu.idle to go up by 2000 per second, so the rate
> converted value is 2000 milliseconds per second which is correct.
>
> The conversion breaks down as
>
> / hz -> seconds
> * 1000 -> milliseconds
>
> This is a common misunderstanding ... it should be captured in a FAQ
> somewhere I guess.
Thanks. Makes perfect sense.
mh
>
> On Thu, 2009-08-06 at 12:54 -0500, Martin Hicks wrote:
> > I went looking today at these metrics, and I'm a bit confused by the
> > values that are printed out. For example:
> >
> > case 23: /* kernel.all.cpu.idle */
> > _pm_assign_utype(_pm_idletime_size, atom,
> > 1000 * (double)proc_stat.idle / proc_stat.hz);
> > break;
> >
> >
> > What's the goal of the multiplication and division by HZ? This just
> > looks plain wrong to me, but maybe I'm missing something. Additional
> > support for this is that the idle metric in PCP advances by 10x what it
> > should (200/sec):
> >
> > mort@laplace:~$ pmdumptext -t 1 kernel.all.cpu.idle
> > Thu Aug 6 13:52:34 ?
> > Thu Aug 6 13:52:35 1989.809
> > Thu Aug 6 13:52:36 2000.010
> >
> > mort@laplace:~$ pminfo -f kernel.all.hz hinv.ncpu
> >
> > kernel.all.hz
> > value 100
> >
> > hinv.ncpu
> > value 2
> >
> >
> > mh
> >
> > _______________________________________________
> > pcp mailing list
> > pcp@xxxxxxxxxxx
> > http://oss.sgi.com/mailman/listinfo/pcp
>
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