[NTLUG:Discuss] Server load average - what is it?

[MadHat]

On Jun 15, 2005, at 6:56 PM, Richard Geoffrion wrote:
> 'w', uptime, procinfo and others will show a system load average in  
> 1,5, and
> 10 minute increments.
>
> but what do the numbers mean??? does a 1.00 mean 100% utilization??  
> if so.
> what does 1.70 mean?  or even 4.77?
>
> Surely they don't mean 170% utilization.   Maybe it means that the  
> server is
> 70% overutilized.  Or maybe  1.7% of total capacity??  Of course  
> that's not
> the case because at 4.77, my server comes to a grinding crawl.. (three
> dirvish jobs looped each other one weekend....oops.)
>
> anyway... I've googled for system load average explained..and no  
> one is
> explaining what the numbers MEAN...meaning what the scale is a  
> scale OF.


Long description...
http://www.teamquest.com/resources/gunther/ldavg1.shtml



The basic answer from the book UNIX Power Tools, tells us on p.726  
The CPU:
"The load average tries to measure the number of active processes at  
any time. As a measure of CPU utilization, the load average is  
simplistic, poorly defined, but far from useless."