3Spoken

December 10, 2006

CPU ‘Steal Time’ – the new statistic in top and vmstat

Filed under: mumblings — NeilW @ 8:35 pm

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.

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5 Comments »

  1. 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 | Reply

  2. […] performance statistic that is very valuable to Netflix is stolen time. Essentially, the steal time cycle counts the amount of time that your VM is ready to run but could […]

    Pingback by Netflix Steals Time In the Cloud – And From Users | ScienceLogic — March 24, 2011 @ 11:37 pm | Reply

  3. […] CPU Steal Time – article on Unspoken Word […]

    Pingback by Episode 013 – Top of Top | Linux In The Shell — August 14, 2012 @ 12:06 pm | Reply

  4. […] performance statistic that is very valuable to Netflix is stolen time. Essentially, the steal time cycle counts the amount of time that your VM is ready to run but could […]

    Pingback by Netflix and Stolen Time • ScienceLogic — June 22, 2016 @ 6:51 pm | Reply


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