Re: [PATCH] i386: single node SPARSEMEM fix

Andrew Morton
2005-09-07T23:49:45Z

"Martin J. Bligh" <mbligh@mbligh.org> wrote:
>
>
>
> --On Wednesday, September 07, 2005 11:27:54 -0700 Dave Hansen <haveblue@us.ibm.com> wrote:
>
> > On Wed, 2005-09-07 at 11:22 -0700, Martin J. Bligh wrote:
> >> CONFIG_NUMA was meant to (and did at one point) support both NUMA and flat
> >> machines. This is essential in order for the distros to support it - same
> >> will go for sparsemem.
> >
> > That's a different issue. The current code works if you boot a NUMA=y
> > SPARSEMEM=y machine with a single node. The current Kconfig options
> > also enforce that SPARSEMEM depends on NUMA on i386.
> >
> > Magnus would like to enable SPARSEMEM=y while CONFIG_NUMA=n. That
> > requires some Kconfig changes, as well as an extra memory present call.
> > I'm questioning why we need to do that when we could never do
> > DISCONTIG=y while NUMA=n on i386.
>
> Ah, OK - makes more sense. However, some machines do have large holes
> in e820 map setups - is not really critical, more of an efficiency
> thing.

Confused. Does all this mean that we want the patch, or not?