Re: [kvm-devel] [PATCH 0/2][KVM] guest time accounting

Avi Kivity wrote:

Laurent Vivier wrote:

quoted

quoted

- perhaps the new fields should be guarded by a #ifdef CONFIG_HYPERVISOR
(selected by CONFIG_KVM)?  that way the (minor) additional overhead is
only incurred if it can possibly be used.  I imagine that our canine
cousin will want to use this as well.
    

There is also a CONFIG_VIRTUALIZATION and a CONFIG_VIRT_CPU_ACCOUNTING
(from
s390 and powerpc) Which one to use ?
  

Are these options for using the kernel as a guest or host?  I'd guess
the former.

I didn't find CONFIG_HYPERVISOR.
The good one seems to be CONFIG_VIRTUALIZATION that is used to activate CONFIG_KVM.

quoted

I'm wondering if we can have a more accurate accounting:

- For the moment we add all system time since the previous entering to
the VCPU
to the guest time (and I guess there is some real system time in it ???)

- Perhaps we can sum nanoseconds spent in the VCPU and add it to
cpustat when
these ns are greater than 1 ms ? (I'm trying to make something in this
way)
  

Ingo (or other guru), could you have a look to the attached patch, it is what I
was thinking about when I wrote this.

Laurent
-- 
------------- Laurent.Vivier@bull.net  --------------
          "Software is hard" - Donald Knuth