diff options
Diffstat (limited to 'mm/slab.c')
| -rw-r--r-- | mm/slab.c | 38 |
1 files changed, 29 insertions, 9 deletions
diff --git a/mm/slab.c b/mm/slab.c index 3318252f657f..bfd654c0ef41 100644 --- a/mm/slab.c +++ b/mm/slab.c @@ -869,6 +869,22 @@ static void __slab_error(const char *function, struct kmem_cache *cachep, dump_stack(); } +/* + * By default on NUMA we use alien caches to stage the freeing of + * objects allocated from other nodes. This causes massive memory + * inefficiencies when using fake NUMA setup to split memory into a + * large number of small nodes, so it can be disabled on the command + * line + */ + +static int use_alien_caches __read_mostly = 1; +static int __init noaliencache_setup(char *s) +{ + use_alien_caches = 0; + return 1; +} +__setup("noaliencache", noaliencache_setup); + #ifdef CONFIG_NUMA /* * Special reaping functions for NUMA systems called from cache_reap(). @@ -1117,7 +1133,7 @@ static inline int cache_free_alien(struct kmem_cache *cachep, void *objp) * Make sure we are not freeing a object from another node to the array * cache on this cpu. */ - if (likely(slabp->nodeid == node)) + if (likely(slabp->nodeid == node) || unlikely(!use_alien_caches)) return 0; l3 = cachep->nodelists[node]; @@ -1195,7 +1211,7 @@ static int __cpuinit cpuup_callback(struct notifier_block *nfb, list_for_each_entry(cachep, &cache_chain, next) { struct array_cache *nc; struct array_cache *shared; - struct array_cache **alien; + struct array_cache **alien = NULL; nc = alloc_arraycache(node, cachep->limit, cachep->batchcount); @@ -1207,9 +1223,11 @@ static int __cpuinit cpuup_callback(struct notifier_block *nfb, if (!shared) goto bad; - alien = alloc_alien_cache(node, cachep->limit); - if (!alien) - goto bad; + if (use_alien_caches) { + alien = alloc_alien_cache(node, cachep->limit); + if (!alien) + goto bad; + } cachep->array[cpu] = nc; l3 = cachep->nodelists[node]; BUG_ON(!l3); @@ -3590,13 +3608,15 @@ static int alloc_kmemlist(struct kmem_cache *cachep) int node; struct kmem_list3 *l3; struct array_cache *new_shared; - struct array_cache **new_alien; + struct array_cache **new_alien = NULL; for_each_online_node(node) { - new_alien = alloc_alien_cache(node, cachep->limit); - if (!new_alien) - goto fail; + if (use_alien_caches) { + new_alien = alloc_alien_cache(node, cachep->limit); + if (!new_alien) + goto fail; + } new_shared = alloc_arraycache(node, cachep->shared*cachep->batchcount, |