From mboxrd@z Thu Jan 1 00:00:00 1970 Received: with ECARTIS (v1.0.0; list linux-mips); Mon, 09 Jan 2006 21:20:58 +0000 (GMT) Received: from mail-out.m-online.net ([212.18.0.9]:2758 "EHLO mail-out.m-online.net") by ftp.linux-mips.org with ESMTP id S8133646AbWAIVUi (ORCPT ); Mon, 9 Jan 2006 21:20:38 +0000 Received: from mail01.m-online.net (svr21.m-online.net [192.168.3.149]) by mail-out.m-online.net (Postfix) with ESMTP id 5F5A9708CE; Mon, 9 Jan 2006 22:23:40 +0100 (CET) X-Auth-Info: 9rjmi9LVaZAfXEmq1oWowzyjKRYS8/8gJ+kKZWZYKBM= X-Auth-Info: 9rjmi9LVaZAfXEmq1oWowzyjKRYS8/8gJ+kKZWZYKBM= X-Auth-Info: 9rjmi9LVaZAfXEmq1oWowzyjKRYS8/8gJ+kKZWZYKBM= Received: from mail.denx.de (p54966F34.dip.t-dialin.net [84.150.111.52]) by smtp-auth.mnet-online.de (Postfix) with ESMTP id 46146B96D9; Mon, 9 Jan 2006 22:23:40 +0100 (CET) Received: from atlas.denx.de (atlas.denx.de [10.0.0.14]) by mail.denx.de (Postfix) with ESMTP id D7A556D00A8; Mon, 9 Jan 2006 22:23:39 +0100 (MET) Received: from atlas.denx.de (localhost.localdomain [127.0.0.1]) by atlas.denx.de (Postfix) with ESMTP id C8289353A66; Mon, 9 Jan 2006 22:23:39 +0100 (MET) To: "Kevin D. Kissell" cc: "Sathesh Babu Edara" , linux-mips@linux-mips.org From: Wolfgang Denk Subject: Re: [processor frequency] Mime-version: 1.0 Content-type: text/plain; charset=ISO-8859-1 Content-transfer-encoding: 8bit In-reply-to: Your message of "Mon, 09 Jan 2006 10:00:48 +0100." <005a01c614fb$2fe76b00$10eca8c0@grendel> Date: Mon, 09 Jan 2006 22:23:39 +0100 Message-Id: <20060109212339.C8289353A66@atlas.denx.de> 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: 9826 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: wd@denx.de Precedence: bulk X-list: linux-mips In message <005a01c614fb$2fe76b00$10eca8c0@grendel> you wrote: > There is no "ideal" value for a given processor frequency. > The lower the value, the less interrupt processing overhead, > but the slower the response time to events that are detected > or serviced during clock interrupts. 1000 HZ *may* be a sensible > value (I have my doubts, personally) for 2+ GHz PC processors, > but it's excessive (IMHO) for a 200MHz processor and unworkable > for a 20MHz CPU. I think that 100HZ is still a reasonable value > for an embedded RISC CPU, but the "ideal" value is going to > be a function of the application. We did some tests of the performance impact of 100 vs. 1000 Hz clock frequency on low end systems (50 MHz PowerPC); for details please see http://www.denx.de/wiki/view/Know/Clock100vs1000Hz Best regards, Wolfgang Denk -- Software Engineering: Embedded and Realtime Systems, Embedded Linux Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd@denx.de Our missions are peaceful -- not for conquest. When we do battle, it is only because we have no choice. -- Kirk, "The Squire of Gothos", stardate 2124.5