Messages in this thread | | | Date | Fri, 27 Sep 2002 17:59:48 +0200 | From | Manfred Spraul <> | Subject | Re: [patch 3/4] slab reclaim balancing |
| |
Andrew Morton wrote: >> >>Is that actually the right approach? For large objects, it would be >>possible to cripple the freeable slabs list, and to perform the cache >>hit optimization (i.e. per-cpu LIFO) in page_alloc.c, but that doesn't >>work with small objects. > > > Well with a, what? 100:1 speed ratio, we'll generally get best results > from optimising for locality/recency of reference. > You misunderstood me:
AFAICS slab.c has 2 weaks spots: * cache hit rates are ignored on UP, and for objects > PAGE_SIZE on both SMP and UP. * freeable pages are not returned efficiently to page_alloc.c, neither on SMP nor on UP. On SMP, this is a big problems, because the cache_chain_semaphore is overloaded.
I just wanted to say that a hotlist in page_alloc.c is not able to replace a hotlist in slab.c, because many objects are smaller than page size. Both lists are needed.
-- Manfred
- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |