On 1/14/2010 1:12 PM, fortin.pierre@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.