Re: [PATCH] slob: poor man's NUMA support.

Nish Aravamudan
2007-06-26T19:17:24Z

On 6/26/07, Christoph Lameter <clameter@sgi.com> wrote:
> On Tue, 26 Jun 2007, Nish Aravamudan wrote:
>
> > > No. alloc_pages follows memory policy. alloc_pages_node does not. One of
> > > the reasons that I want a new memory policy layer are these kinds of
> > > strange uses.
> >
> > What would break by changing, in alloc_pages_node()
> >
> > if (nid < 0)
> > nid = numa_node_id();
> >
> > to
> >
> > if (nid < 0)
> > return alloc_pages_current(gfp_mask, order);
> >
> > beyond needing to make alloc_pages_current() defined if !NUMA too.
>
> It would make alloc_pages_node obey memory policies instead of only
> following cpuset constraints. An a memory policy may redirect the
> allocation from the local node ;-).

heh, true true.

Hrm, I guess the simplest looking solution is rarely the best. Could
we add more smarts in alloc_pages_current() to make GFP_THISNODE be
equivalent to bind_zonelist(thisnode_only_mask)? I'll keep thinking,
maybe I'll come up with something.

Thanks,
Nish