Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933409AbZJNOQZ (ORCPT ); Wed, 14 Oct 2009 10:16:25 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S933376AbZJNOQY (ORCPT ); Wed, 14 Oct 2009 10:16:24 -0400 Received: from smtp2.ultrahosting.com ([74.213.174.253]:35631 "EHLO smtp.ultrahosting.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S933221AbZJNOQY (ORCPT ); Wed, 14 Oct 2009 10:16:24 -0400 Date: Wed, 14 Oct 2009 10:08:12 -0400 (EDT) From: Christoph Lameter X-X-Sender: cl@gentwo.org To: Mel Gorman cc: David Rientjes , Pekka Enberg , Tejun Heo , linux-kernel@vger.kernel.org, Mathieu Desnoyers , Zhang Yanmin Subject: Re: [this_cpu_xx V6 7/7] this_cpu: slub aggressive use of this_cpu operations in the hotpaths In-Reply-To: <20091014133457.GB5027@csn.ul.ie> Message-ID: References: <4AD307A5.105@kernel.org> <84144f020910120614r529d8e4em9babe83a90e9371f@mail.gmail.com> <4AD4D8B6.6010700@cs.helsinki.fi> <20091014133457.GB5027@csn.ul.ie> User-Agent: Alpine 1.10 (DEB 962 2008-03-14) 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: 1432 Lines: 30 The test did not include the irqless patch I hope? On Wed, 14 Oct 2009, Mel Gorman wrote: > Small gains in the User, System and Elapsed times with this-cpu patches > applied. It is interest to note for the mean times that the patches more > than close the gap between SLUB and SLAB for the most part - the > exception being User which has marginally better performance. This might > indicate that SLAB is still slightly better at giving back cache-hot > memory but this is speculation. The queuing in SLAB allows a better cache hot behavior. Without a queue SLUB has a difficult time improvising cache hot behavior based on objects restricted to a slab page. Therefore the size of the slab page will affect how much "queueing" SLUB can do. > The patches mostly improve the performance of netperf UDP_STREAM by a good > whack so the patches are a plus here. However, it should also be noted that > SLAB was mostly faster than SLUB, particularly for large packet sizes. Refresh > my memory, how do SLUB and SLAB differ in regards to off-loading large > allocations to the page allocator these days? SLUB offloads allocations > 8k to the page allocator. SLAB does create large slabs. -- 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/