Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S971559AbXFHWek (ORCPT ); Fri, 8 Jun 2007 18:34:40 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S971479AbXFHWdl (ORCPT ); Fri, 8 Jun 2007 18:33:41 -0400 Received: from netops-testserver-3-out.sgi.com ([192.48.171.28]:57873 "EHLO relay.sgi.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S971473AbXFHWdk (ORCPT ); Fri, 8 Jun 2007 18:33:40 -0400 Date: Fri, 8 Jun 2007 15:33:39 -0700 (PDT) From: Christoph Lameter X-X-Sender: clameter@schroedinger.engr.sgi.com To: "Keshavamurthy, Anil S" cc: Andrew Morton , linux-kernel@vger.kernel.org, ak@suse.de, gregkh@suse.de, muli@il.ibm.com, asit.k.mallick@intel.com, suresh.b.siddha@intel.com, arjan@linux.intel.com, ashok.raj@intel.com, shaohua.li@intel.com, davem@davemloft.net Subject: Re: [Intel-IOMMU 02/10] Library routine for pre-allocat pool handling In-Reply-To: <20070608201200.GA641@linux-os.sc.intel.com> Message-ID: References: <20070606185658.138237000@askeshav-devel.jf.intel.com> <20070606190042.510643000@askeshav-devel.jf.intel.com> <20070607162726.2236a296.akpm@linux-foundation.org> <20070608182156.GA24865@linux-os.sc.intel.com> <20070608120107.245eba96.akpm@linux-foundation.org> <20070608201200.GA641@linux-os.sc.intel.com> 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: 875 Lines: 18 On Fri, 8 Jun 2007, Keshavamurthy, Anil S wrote: > > You _seem_ to be saying that the resource pools are there purely for > > alloc/free performance reasons. If so, I'd be skeptical: slab is pretty > > darned fast. > We need several objects of size say( 4 * sizeof(u64)) and reuse > them in dma map/unmap api calls for managing io virtual allocation address that > this driver has dished out. Hence having pool of objects where we put > the element in the linked list and and get it from the linked list is pretty > fast compared to slab. SLUB also manages objects using a linked list. Is there a real performance difference? - 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/