Re: [PATCH] Enhance perf to collect KVM guest os statistics from host side

[Ingo Molnar <mingo@elte.hu>]

* Avi Kivity <avi@redhat.com> wrote:

> On 03/16/2010 12:50 PM, Ingo Molnar wrote:
> >
> >>I'm confused - initrd seems to be guest-side.  I was talking about the host
> >>side.
> >host side doesnt need much support - just some client capability in perf
> >itself. I suspect vmchannels are sufficiently flexible and configuration-free
> >for such purposes? (i.e. like a filesystem in essence)
> 
> I haven't followed vmchannel closely, but I think it is.  vmchannel is 
> terminated in qemu on the host side, not in the host kernel.  So perf would 
> need to connect to qemu.

Hm, that sounds rather messy if we want to use it to basically expose kernel 
functionality in a guest/host unified way. Is the qemu process discoverable in 
some secure way? Can we trust it? Is there some proper tooling available to do 
it, or do we have to push it through 2-3 packages to get such a useful feature 
done?

( That is the general thought process how many cross-discipline useful
  desktop/server features hit the bit bucket before having had any chance of
  being vetted by users, and why Linux sucks so much when it comes to feature
  integration and application usability. )

	Ingo