[CentOS] High load since passing from rhas3 to centos4.8

Thu Jan 14 20:37:58 UTC 2010
Les Mikesell <lesmikesell at gmail.com>

On 1/14/2010 1:12 PM, fortin.pierre at bell.ca wrote:
> We are migrating HP servers from RHAS3 to centos 4.8. Since, the load
> average is reaching really high values. Under usage we see loads of
> 15-20 instead of the 0.5-1.5 we were used to.
>
> I searched a lot for information on such an issue. Iostat, vmstat, top,
> ps. But I don’t get significant hint.
>
> Cpu usage remains low, IO wait remains low, no disks are lagging, no
> swap usage.
>
> Are there some tool / other way to diagnose why the load average is
> high? Like which processes are waiting, where they are stuck. Are there
> calls to drivers or system process that are slow?

I don't have an answer but out of curiosity, why would you move to a 4.x 
instead of 5.x now?

You might be able to do some ps snapshots to see the process in R state, 
which is what the load average should be counting.  That might be 
computed differently between the 2.4 and 2.6 kernels.

-- 
   Les Mikesell
    lesmikesell at gmail.com