[rrd-users] Re: Monitoring CPU stats on Linux? Watch your jiffies.

Fabien Wernli wernli at in2p3.fr
Sat Dec 10 21:52:57 MET 2005


Hi,

On Fri, Dec 09, 2005 at 12:59:29PM -0700, Clay Chambers wrote:
> It seems that under extremely heavy load, the idle counter actually
> goes down due to rounding.  (I'm not completely certain that it's due
> to rounding, but that's the most plausible cause I've come up with.) 
> The result is that your CPU utilization graphs could show 0% when
> they're actually at 100% utilization.

I have constant inaccuracies watching /proc/stats. However in my experience
they happen mostly during heavy io_wait activity.

See example:

http://faxm0dem.org/tmp/cpu.png

--
Unsubscribe mailto:rrd-users-request at list.ee.ethz.ch?subject=unsubscribe
Help        mailto:rrd-users-request at list.ee.ethz.ch?subject=help
Archive     http://lists.ee.ethz.ch/rrd-users
WebAdmin    http://lists.ee.ethz.ch/lsg2.cgi



More information about the rrd-users mailing list