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I have several VM hosted by a private service provider. I know they are using VMWare and I believe most of my VM are on a shared hosting.

I noticed that the steal time for all my machines is always 0%.

As far as my understanding of CPU steal times goes (virtualization is not my field) this steal time should show how much time my virtual CPU is waiting for the real CPU.

So what could I deduce from 0% steal time?

  1. My VM is on a dedicated machine, or at least a very underused machine?
  2. steal time is "fake" or artificially set to 0 by provider?
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  • VMware is a company not a product, which of their many products are you talking about - and can you add that to your tag please as right now it's meaningless.
    – Chopper3
    Nov 23 '18 at 12:59
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You should deduce that the hardware is not overloaded. Pretty much like that. Not necessarily a DEDICATED (to the VM) machine, but one that has enough capacity. The only reason that ever goes up is if you have more VCPU than real cores (so that there is a chance for waiting) and those VCPU are busy enough to cause waiting. Which generally is a sign of a TREMENDOUSLY overloaded host.

1
  • Agreed, that 0% is many times desired by designers of VM centers.
    – Overmind
    Aug 28 '20 at 11:28
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Unless you have some other indications that there are problems, you should assume the steal time is 0% and the physical host isn't very loaded for whatever reason.

1

The Linux driver for VMWare guest support didn't support steal time accounting until 5.7.

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  • It's probably more accurate to say that Linux did not support steal time accounting for VMware guests. This is a patch to the Linux kernel, after all. Now the question is, which version of Linux was it accepted into? Aug 28 '20 at 18:24
  • It's also the name of the paravirtual driver. $ git describe --contains ab02bb3f55f58e7608a88188000c3353398ebe3b v5.7-rc1~159^2~2
    – wenjianhn
    Aug 29 '20 at 13:50
  • 1
    If you intended to refer to the LInux kernel driver and not VMware, then you should say so explicitly. The way it currently reads is confusing. Aug 29 '20 at 17:09
  • I don't think so. The link I gave had the context. The title of the link starts with "x86/vmware".
    – wenjianhn
    Aug 31 '20 at 2:00
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    It should not be necessary to click through the link to understand your answer. Many of our readers cannot click the links or the site is blocked for them. And the link could die later. Aug 31 '20 at 2:54

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