In between dying quietly from acute viral nasopharyngitis (as supplied in various varieties by my three year old daughter) and trying to earn a crust or two I’ve been playing with the Amazon Elastic Compute Cloud (EC2).
One of the things you notice when you run up a relatively recent Linux distribution is that there is a new CPU %age shown when you run ‘top’. The mysterious ’st’.
It turns out that this stands for ‘Steal Time’ and is the amount of real cpu that the Xen Hypervisor has allocated to tasks other than running your Virtual Machine (such as somebody else’s VM…).
So if your AMI doesn’t have this statistic in ‘top’, and isn’t reporting ‘Stolen CPU ticks’ in ‘vmstat -s’, then you need to upgrade your ‘procps’ tools to a later version.
Your description of steal time is almost correct
Steal time is the time that (1) the CPU had something runnable, but (2) the hypervisor chose to run something else instead.
Time where your virtual machine did not want to run anyway (and the hypervisor runs something else) do not count as steal time.
Comment by Rik van Riel — April 12, 2007 @ 11:59 pm
Thanks for information.
many interesting things
Celpjefscylc
Comment by celpjefscycle — January 12, 2008 @ 12:29 am