Re: NUMA policy interface

Andi Kleen
2005-08-05T09:16:30Z

On Thu, Aug 04, 2005 at 04:49:33PM -0700, Christoph Lameter wrote:
> On Fri, 5 Aug 2005, Andi Kleen wrote:
>
> > None of them seem very attractive to me. I would prefer to just
> > not support external accesses keeping things lean and fast.
>
> That is a surprising statement given what we just discussed. Things
> are not lean and fast but weirdly screwed up. The policy layer is
> significantly impacted by historical contingencies rather than designed in
> a clean way. It cannot even deliver the functionality it was designed to
> deliver (see BIND).

That seems like a unfair description to me. While things are not
perfect they are definitely not as bad as you're trying to paint them.

>
> > Individual physical page migration is quite different from
> > address space migration.
>
> Address space migration? That is something new in this discussion. So
> could you explain what you mean by that? I have looked at page migration
> in a variety of contexts and could not see much difference.

MCE page migration just puts a physical page to somewhere else.
memory hotplug migration does the same for multiple pages from
different processes.

Page migration like you're asking for migrates whole processes.

-Andi