high load average, no cpu or ram usage

[bangsters]

Hey,

I was comparing servers, and I noticed that 2 of my servers running whm are constantly around 7-15 load average eventhough cpu usage is close to none. There is not much RAM usage and swap is unused. I have checked processes, and out of around 200, 1-5 are running, with 1 zombie, and the rest sleeping. iowait varies from 5% to 40% (sometimes spikes to 50%) but even on low iowait the load average still sits at 8.

The servers are both 2 x dual cores with 8GB RAM running latest whm on centos 32bit platform. A similar setup with only 4GB on another box produces around 1.5load all day, which is puzzling.

Any suggestions? I compared httpd.conf, my.cnf, and even easyapache compilation and both servers are near identical in setup. I can't think of any other avenue to check.

[keddie]

I've just been dealing with a similar issue on my dedi. If CPU and RAM are looking OK then you might have an IO / disk issue.

I would recommend installing the Sysstat suite of resource monitoring tools:

yum install sysstat

which will install iostat and some other handy scripts.

I started a thread on this subject over on linuxquestions.org and got some really good help and advice:

Troubleshooting high load - Possible IO / RAID issue? - LinuxQuestions.org

This link outlined the tools availble for diagnosing load issues on centos / RHL:

Red Hat Enterprise Linux-Specific Information


These links also helped me get to grips with iostat:

iostat and disk utilization monitoring nirvana
Eric Bergen » The difference between %iowait from sar and %util from iostat

Let me know how you get on.

Ked

[bangsters]

Thanks for the link. WHen you were having the same issue, what was the average IO you were getting? Our IO varies anywhere from 2% to 50%. However, load avegare still shows around 5-6 even if the io is very low.

We already have systat and use it as well, but thanks for the info I'll read over the links you sent over.

Thanks again!