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:user-659655b2ea05@xymon.invalid]
Sent: Friday, February 16, 2007 12:31 PM
To: user-ae9b8668bcde@xymon.invalid
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