[hobbit] CPU Utilization, Less Averaging

Why do users think that the load average graph (which measures the average length of the CPU run queue) should correlate with the CPU utilization (busy time divided by available time)? The values in each graph are calculated very differently.

Just wondering...

GLH

From: James Wade [mailto:jkwade at futurefrontiers.com] 
Sent: Friday, February 16, 2007 12:31 PM
To: hobbit at hswn.dk
Subject: [hobbit] CPU Utilization, Less Averaging



Can I set the vmstat collection to average less

and collect more data points? The users here

don't agree with the CPU Utilization Graph,

they don't like the way the Average doesn't

fluctuate much.

 

Basically, they are comparing the Load graph

with the Utilization Graph and want to see the

graph correlate more with the Load Graph.

 

My understanding is that the Utilization Graph

is using a 5 minute cpu idle average from vmstat.

 

Can I change vmstat to take a 15 second average

as an example, and do more counts so more datapoints 

are graphed?

 

Any suggestions would be appreciated.

 

Thanks...James