Strange load average with Nagios 3

[Andreas Ericsson]

Yann Jouanin wrote:
> Hello everyone,
> 
> I noticed a strange behavior on our Nagios 3 monitoring servers. On the four
> servers, the load average is reproduction a periodic pattern (every four
> hours approximately) and the pattern look like a "roller coaster".
> 
> Here is an example on load observed :
> http://www.intelunix.fr/nagios/load.png
> 
> Has anyone the same observation ?

I've never seen anything like it before. Does the 4-hour interval coincide
with your check-interval? Does it align with some performance-data processing?

> Can something in Nagios behavior explain
> this load ?

Not really, no. I suppose a database logging application could display a load
pattern such as this if it manages its tables really poorly and then vacuums
them at the peak of the load, but since you mentioned nothing about NDOUtils
or anything similar I'll just assume you have no such things installed.

> Our servers are running different Linux distributions and we spot out the
> fact that the pattern is certainly due to Nagios.
> 

How did you ascertain this? Sorry for being skeptical, but I've seen
"Oh I'm really, really sure" followed by "oops turned out I was wrong"
too many times to trust other's eyes ;-)

-- 
Andreas Ericsson                   andreas.ericsson at op5.se
OP5 AB                             www.op5.se
Tel: +46 8-230225                  Fax: +46 8-230231

Considering the successes of the wars on alcohol, poverty, drugs and
terror, I think we should give some serious thought to declaring war
on peace.

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