Re: [gentoo-user] OT: Can a linux vmware guest tell if its host is CPU constrained?

[Jeremi Piotrowski <jeremi.piotrowski@gmail.com>]

On Thu, Jul 30, 2020 at 2:52 AM Adam Carter <adamcarter3@gmail.com> wrote:
>>
>> > So should I run something like: date ; time <some command that runs at
>> > 100%CPU for a minute> ; date ?
>>
>> No, date will pull from your RTC, which is usually kept up to date with an asynchronous
>> counter.
>>
>> First check GNU top(1) and look in the %Cpu line for "st." That is % CPU time stolen. If it is
>> nonzero then the guest time's accounting is probably working. It's not typical for the
>> hypervisor to hide this information. It's really important for load balancing.
>
>
> Thanks for that. I haven't seen any non-zero stolen time yet, however.
>
> FWIW vmstat also shows stolen time.

Stolen time reporting through vmstat/top only works on xen and kvm
hypervisors, it wasn't
implemented for vmware. It actually looks like it was finally
submitted for linux v5.7
(https://lore.kernel.org/lkml/20200331100353.GA37509@gmail.com/).

If you want those numbers for older kernels, fetch this repository:
https://github.com/dagwieers/vmguestlib
and run vmguest-stats. You'll also need open-vm-tools installed. Have
used this many times in the past and
the numbers are good.