Re: [PATCH V4 0/7] x86/intel_rdt: Intel Cache Allocation Technology

[Ingo Molnar <mingo@kernel.org>]

* Luck, Tony <tony.luck@intel.com> wrote:

> > The CAT thing was annoying already, but at least one 
> > can find that in the SDM, this RDT thing, not a single 
> > mention.
> 
> The problems of development at the bleeding edge. Would 
> you rather Linux sat on the sidelines until there are 
> enough Google hits from other users of new features?

Well, we'd prefer there to be A) published documentation, 
or, lacking published documentation, there be B) a coherent 
technical description within the code itself what the 
purpose is and how it all works conceptually (minus the 
buzzwords), so that we have a common starting point when 
reviewing it.

>    Technology: Intel Resource Director Technology
> 
>    Description: Allows the hypervisor to monitor Last Level Cache usage at the application
>    and VM levels.
> 
>    Benefit: Helps to improve performance and efficiency by providing better
>    information for scheduling, load balancing, and workload migration
> 
> Which isn't any help in evaluating this patch series :-(

No, but it already tells us more than the 0/7 description 
of the patch series did! It should be possible to improve 
on that.

Maintainers reverse engineering the implementation is an 
inefficient approach.

Thanks,

	Ingo