From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail6.bemta12.messagelabs.com (mail6.bemta12.messagelabs.com [216.82.250.247]) by kanga.kvack.org (Postfix) with ESMTP id 738526B0047 for ; Fri, 2 Dec 2011 06:36:48 -0500 (EST) Received: by vcbfk26 with SMTP id fk26so2925386vcb.14 for ; Fri, 02 Dec 2011 03:36:46 -0800 (PST) Message-ID: <1322825802.2607.10.camel@edumazet-laptop> Subject: Re: [PATCH 1/3] slub: set a criteria for slub node partial adding From: Eric Dumazet Date: Fri, 02 Dec 2011 12:36:42 +0100 In-Reply-To: <1322814189-17318-1-git-send-email-alex.shi@intel.com> References: <1322814189-17318-1-git-send-email-alex.shi@intel.com> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8bit Mime-Version: 1.0 Sender: owner-linux-mm@kvack.org List-ID: To: Alex Shi Cc: cl@linux.com, penberg@kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org Le vendredi 02 dA(C)cembre 2011 A 16:23 +0800, Alex Shi a A(C)crit : > From: Alex Shi > > Times performance regression were due to slub add to node partial head > or tail. That inspired me to do tunning on the node partial adding, to > set a criteria for head or tail position selection when do partial > adding. > My experiment show, when used objects is less than 1/4 total objects > of slub performance will get about 1.5% improvement on netperf loopback > testing with 2048 clients, wherever on our 4 or 2 sockets platforms, > includes sandbridge or core2. > > Signed-off-by: Alex Shi > --- > mm/slub.c | 18 ++++++++---------- > 1 files changed, 8 insertions(+), 10 deletions(-) > netperf (loopback or ethernet) is a known stress test for slub, and your patch removes code that might hurt netperf, but benefit real workload. Have you tried instead this far less intrusive solution ? if (tail == DEACTIVATE_TO_TAIL || page->inuse > page->objects / 4) list_add_tail(&page->lru, &n->partial); else list_add(&page->lru, &n->partial); -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org