Re: NUMA policy issues with ZONE_MOVABLE

Christoph Lameter
2007-07-26T18:03:59Z

On Thu, 26 Jul 2007, Mel Gorman wrote:

> /* policy_zone is the lowest zone index that is present on all nodes */
>
> Right?

Nope. In a 4 node x86_64 opteron configuration with 8GB memory in 4 2GB
chunks you could have

node 0 ZONE_DMA, ZONE_DMA32 <2GB
node 1 ZONE_DMA32 <4GB
node 2 ZONE_NORMAL <6GB
node 3 ZONE_NORMAL <8GB

So the highest zone gets partitioned off? We only have ZONE_MOVABLE on
nodes 2 and 3?

There are some other weirdnesses possible with ZONE_MOVABLE on !NUMA.

1GB i386 system

ZONE_DMA
ZONE_NORMAL <900k
ZONE_HIGHEMEM 100k size

ZONE_MOVABLE can then only use 100k?