CONFIG_NUMA and DISCONTIG inconsistencies

[Dave Hansen]

On Mon, 2005-03-21 at 14:12 -0600, Olof Johansson wrote:
> I think we have machines with discontigous memory (due to I/O holes)
> without having NUMA support on the machines, i.e. some POWER3/RS64
> boxes.

DISCONTIGMEM only provides discontiguous mem_maps between different
zones.  The mem_map[] inside of any single zone is contiguous.  As I
understand it, most of the 64-bit arches keep all of their memory in one
zone, and they only separate memory into different zones when there are
multiple NUMA nodes.  

I guess don't understand what DISCONTIGMEM provides on !NUMA machines,
even like the POWER3 machines.

-- Dave