[wellylug] High load averages but no apparent cause

[Michael Hudson-Doyle]

On 22 March 2010 16:49, David Harrison <david.harrison at stress-free.co.nz> wrote:
> Hi,
> Has anyone experienced high-load averages but haven't been able to see
> processes that are causing it?
> I've got an Ubuntu Server 9.10 instance who's load average ranges between
> 1.0 and 3.0 for most of the day, yet tools like top and iostat don't reveal
> any issues.
> i.e. The load averages can be up around 1.5 whilst the maximum process
> viewed in top is sitting at 5% of the CPU.
> Anyone know of any other good tools for identifying the cause of server load
> if the obvious ones fail?

A high load average can be a sign of lots of processes waiting for IO
as well as processes waiting for CPU... does 'vmstat' show lots of
iowait?

Cheers,
mwh