Re: [PATCH 01/02] cpuset memory spread slab cache filesys

[Christoph Lameter <clameter@engr.sgi.com>]

On Mon, 27 Feb 2006, Andi Kleen wrote:

> On Monday 27 February 2006 21:36, Christoph Lameter wrote:
> 
> > On the other hand setting memory policy to MPOL_INTERLEAVE already 
> > provides that functionality.
> 
> Yes, but not selective for these slabs caches. I think it would be useful
> if we could interleave inodes/dentries but still keep a local policy for
> normal program memory.

We could make the memory policy only apply if the SLAB_MEM_SPREAD option 
is set:

Index: linux-2.6.16-rc4-mm2/mm/slab.c
===================================================================
--- linux-2.6.16-rc4-mm2.orig/mm/slab.c	2006-02-24 10:33:54.000000000 -0800
+++ linux-2.6.16-rc4-mm2/mm/slab.c	2006-02-27 12:54:52.000000000 -0800
@@ -2871,7 +2871,9 @@ static void *alternate_node_alloc(struct
 	if (in_interrupt())
 		return NULL;
 	nid_alloc = nid_here = numa_node_id();
-	if (cpuset_do_slab_mem_spread() && (cachep->flags & SLAB_MEM_SPREAD))
+	if (!cachep->flags & SLAB_MEM_SPREAD)
+		return NULL;
+	if (cpuset_do_slab_mem_spread())
 		nid_alloc = cpuset_mem_spread_node();
 	else if (current->mempolicy)
 		nid_alloc = slab_node(current->mempolicy);