From mboxrd@z Thu Jan 1 00:00:00 1970 Received: with ECARTIS (v1.0.0; list linux-mips); Mon, 17 Oct 2005 17:07:43 +0100 (BST) Received: from extgw-uk.mips.com ([62.254.210.129]:64524 "EHLO bacchus.net.dhis.org") by ftp.linux-mips.org with ESMTP id S8133583AbVJQQHR (ORCPT ); Mon, 17 Oct 2005 17:07:17 +0100 Received: from dea.linux-mips.net (localhost.localdomain [127.0.0.1]) by bacchus.net.dhis.org (8.13.4/8.13.1) with ESMTP id j9HG79UJ017173; Mon, 17 Oct 2005 17:07:09 +0100 Received: (from ralf@localhost) by dea.linux-mips.net (8.13.4/8.13.4/Submit) id j9HG79su017172; Mon, 17 Oct 2005 17:07:09 +0100 Date: Mon, 17 Oct 2005 17:07:08 +0100 From: Ralf Baechle To: kernel coder Cc: linux-mips@linux-mips.org Subject: Re: How to improve performance of 2.6 kernel Message-ID: <20051017160708.GA8613@linux-mips.org> References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.4.2.1i Return-Path: X-Envelope-To: <"|/home/ecartis/ecartis -s linux-mips"> (uid 0) X-Orcpt: rfc822;linux-mips@linux-mips.org Original-Recipient: rfc822;linux-mips@linux-mips.org X-archive-position: 9243 X-ecartis-version: Ecartis v1.0.0 Sender: linux-mips-bounce@linux-mips.org Errors-to: linux-mips-bounce@linux-mips.org X-original-sender: ralf@linux-mips.org Precedence: bulk X-list: linux-mips On Mon, Oct 17, 2005 at 04:29:44AM -0700, kernel coder wrote: > I have just ported linux kernel 2.6.10 for MIPS4Kc-core board.Before > porting 2.6 kernel ,2.4.20 was running on this board. When I took > benchmarks for both the kernels for comparison, I found out that > linux-2.4.20 was giving much better results than linux-2.6.10. The > specs for the board are as follows: > > -------------------------------------------------------------- > 133MHz MIPS4kc How many TLB entries does your 4Kc have? 2.6 is hitting the TLB harder and system that have small TLBs tend to suffer from that at the bottom line even though all the other benefits of 2.6. It would be interesting to see lmbench numbers for the system configurations you've tested. Lmbench is a well defined workload that's proven useful in isolating such issues. Thanks, Ralf