From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S264362AbUEDNNC (ORCPT ); Tue, 4 May 2004 09:13:02 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S264363AbUEDNNC (ORCPT ); Tue, 4 May 2004 09:13:02 -0400 Received: from e33.co.us.ibm.com ([32.97.110.131]:7632 "EHLO e33.co.us.ibm.com") by vger.kernel.org with ESMTP id S264362AbUEDNNA (ORCPT ); Tue, 4 May 2004 09:13:00 -0400 Date: Tue, 4 May 2004 08:12:23 -0500 From: "Jose R. Santos" To: Andrew Morton Cc: linux-kernel@vger.kernel.org, anton@samba.org, dheger@us.ibm.com Subject: Re: [PATCH] dentry and inode cache hash algorithm performance changes. Message-ID: <20040504131223.GA28009@austin.ibm.com> References: <20040430191539.GC14271@rx8.ibm.com> <20040430131832.45be6956.akpm@osdl.org> <20040430205701.GG14271@rx8.ibm.com> <20040430213324.GK14271@rx8.ibm.com> <20040430150256.25735762.akpm@osdl.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20040430150256.25735762.akpm@osdl.org> User-Agent: Mutt/1.5.5.1+cvs20040105i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org * Andrew Morton [2004-04-30 15:02:56 -0700]: > Also, I'd be interested in understanding what the input to the hashing > functions looked like in this testing. It could be that the new hash just > happens to work well with one particular test's dataset. Please convince > us otherwise ;) Andrew - Is there any workload you want me to run to show that this hash function is going to be equal or better that the one already provided in Linux? Remember that my claim is not the this hash function will be better for every IO workload. I claim it should not have worst performance than the default hash function but on some workloads it should perform better. The workloads that this should show improvements are those that use GB of memory to store inode and dentry cache data. I have run some test on my old BP6 machine and other than a small improvements while running find, I did not see any improvements but no regressions either. Again, if you have a particular workload in mind, Ill be happy to run it on some of my systems. Thanks, -JRS