Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758364AbXHUXis (ORCPT ); Tue, 21 Aug 2007 19:38:48 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755495AbXHUXil (ORCPT ); Tue, 21 Aug 2007 19:38:41 -0400 Received: from netops-testserver-4-out.sgi.com ([192.48.171.29]:60365 "EHLO relay.sgi.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1755215AbXHUXil (ORCPT ); Tue, 21 Aug 2007 19:38:41 -0400 Date: Tue, 21 Aug 2007 16:38:39 -0700 (PDT) From: Christoph Lameter X-X-Sender: clameter@schroedinger.engr.sgi.com To: Mathieu Desnoyers cc: akpm@linux-foundation.org, linux-kernel@vger.kernel.org, mingo@redhat.com Subject: Re: [PATCH] SLUB use cmpxchg_local In-Reply-To: <20070821232133.GB29691@Krystal> Message-ID: References: <20070820201822.597720007@polymtl.ca> <20070820204126.GA22507@Krystal> <20070820212922.GA27011@Krystal> <20070820215413.GA28452@Krystal> <20070821173849.GA8360@Krystal> <20070821174424.GB8360@Krystal> <20070821232133.GB29691@Krystal> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1010 Lines: 30 On Tue, 21 Aug 2007, Mathieu Desnoyers wrote: > kmalloc(8)/kfree = 112 cycles > kmalloc(16)/kfree = 103 cycles > kmalloc(32)/kfree = 103 cycles > kmalloc(64)/kfree = 103 cycles > kmalloc(128)/kfree = 112 cycles > kmalloc(256)/kfree = 111 cycles > kmalloc(512)/kfree = 111 cycles > kmalloc(1024)/kfree = 111 cycles > kmalloc(2048)/kfree = 121 cycles Looks good. This improves handling for short lived objects about threefold. > kmalloc(4096)/kfree = 650 cycles > kmalloc(8192)/kfree = 1042 cycles > kmalloc(16384)/kfree = 1149 cycles Hmmm... The page allocator is really bad here.... Could we use the cmpxchg_local approach for the per cpu queues in the page_allocator? May have an even greater influence on overall system performance than the SLUB changes. - 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/