Re: [PATCH] i386: single node SPARSEMEM fix

Martin J. Bligh
2005-09-07T18:34:51Z

--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.

M.