[hobbit] CPU Utilization, Not Good

[Henrik Stoerner]

On Fri, Nov 30, 2007 at 11:21:25AM -0600, James Wade wrote:

> I've asked this several times, but I really have not received
> a good answer. Hobbit doesn't really seem to monitor cpu 
> utilization correctly.

Hobbit uses the system's "vmstat" command to determine how much the CPU
is being used. So the blame should go to your vmstat tool - or your
interpretation of the data :-)

> For example, I can look at the load, login to the box, and then
> run top. Top shows that cpu utilization is at 100%, 0% idle time.
> 
> However, the "trends" utilization graph shows 20% cpu utilization.

Hobbit monitors the load as an average over 5 minutes. "top" - at
least when used interactively - has a sample period of a few seconds.
I have some systems where "top" will ALWAYS show the cpu as 100% busy,
because "top" is gobbling up all of the cpu time for itself ....

If you want to see things the way Hobbit does, run "vmstat 2 300", wait 
for it to complete (5 minutes), and look at the cpu-utilisation reported
on the last line.


Henrik