Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760225AbXLUXyn (ORCPT ); Fri, 21 Dec 2007 18:54:43 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755264AbXLUXyg (ORCPT ); Fri, 21 Dec 2007 18:54:36 -0500 Received: from relay1.sgi.com ([192.48.171.29]:47620 "EHLO relay.sgi.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1755112AbXLUXyg (ORCPT ); Fri, 21 Dec 2007 18:54:36 -0500 Date: Fri, 21 Dec 2007 15:54:32 -0800 (PST) From: Christoph Lameter X-X-Sender: clameter@schroedinger.engr.sgi.com To: Ingo Molnar cc: Linus Torvalds , Pekka Enberg , Steven Rostedt , LKML , Andrew Morton , Peter Zijlstra , Christoph Hellwig , "Rafael J. Wysocki" Subject: Re: Major regression on hackbench with SLUB (more numbers) In-Reply-To: <20071221231728.GA28008@elte.hu> Message-ID: References: <1197049846.1645.68.camel@localhost.localdomain> <20071211143336.GA17866@elte.hu> <20071221120908.GA15926@elte.hu> <84144f020712210944q3e0539f8vd8a249f69d456dc7@mail.gmail.com> <20071221231728.GA28008@elte.hu> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1890 Lines: 57 On Sat, 22 Dec 2007, Ingo Molnar wrote: > and the regression seems to be largely fixed! Not only is the hackbench > one fixed, but mmap shows an above-noise improvement as well. > > Acked-by: Ingo Molnar Well lets use the version attached to this patch. It turns out that it is not important to increase the number of partial slabs. Just putting the slab onto the tail of the list does it. > And i hereby nominate Pekka as SLUB/SLAB co-maintainer and spokesperson > ;-) He is already the co-maintainer of the slab allocators. See the MAINTAINERS file. SLUB: Improve hackbench speed Increase the mininum number of partial slabs to keep around and put partial slabs to the end of the partial queue so that they can add more objects. Signed-off-by: Christoph Lameter --- mm/slub.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) Index: linux-2.6/mm/slub.c =================================================================== --- linux-2.6.orig/mm/slub.c 2007-12-21 14:30:11.096324462 -0800 +++ linux-2.6/mm/slub.c 2007-12-21 15:10:17.611022381 -0800 @@ -1611,12 +1611,12 @@ checks_ok: goto slab_empty; /* - * Objects left in the slab. If it - * was not on the partial list before - * then add it. + * Objects left in the slab. If it was not on the partial list before + * then add it. Add it to the end since there is only a single object + * which would make slab_alloc inefficient. */ if (unlikely(!prior)) - add_partial(get_node(s, page_to_nid(page)), page); + add_partial_tail(get_node(s, page_to_nid(page)), page); out_unlock: slab_unlock(page); -- 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/