Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Wed, 21 Aug 2002 15:02:44 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Wed, 21 Aug 2002 15:02:44 -0400 Received: from chaos.analogic.com ([204.178.40.224]:13696 "EHLO chaos.analogic.com") by vger.kernel.org with ESMTP id ; Wed, 21 Aug 2002 15:02:43 -0400 Date: Wed, 21 Aug 2002 15:07:00 -0400 (EDT) From: "Richard B. Johnson" Reply-To: root@chaos.analogic.com To: Mukesh Rajan cc: Richard Zidlicky , linux-kernel@vger.kernel.org Subject: Re: detecting hard disk idleness In-Reply-To: Message-ID: 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 On Wed, 21 Aug 2002, Mukesh Rajan wrote: > this again would mean that i would have to poll the /proc/interrupt file. > i want to avoid polling because of very small poll interval causing > overhead. i am still wondering if this could be implemented with some sort > of interrupt mechanism in linux (kernel interrupting user program or user > program waiting on some signal) > > - mukesh > Hard disk 'idleness' is something you would check at a 1-second interval. As such, its overhead is very small. This is a sample at 1 second intervals during a kernel compile: 11: 4667 4585 IO-APIC-level BusLogic BT-958 11: 4667 4585 IO-APIC-level BusLogic BT-958 11: 4667 4585 IO-APIC-level BusLogic BT-958 11: 4667 4585 IO-APIC-level BusLogic BT-958 11: 4667 4585 IO-APIC-level BusLogic BT-958 11: 4667 4585 IO-APIC-level BusLogic BT-958 11: 4667 4585 IO-APIC-level BusLogic BT-958 11: 4667 4585 IO-APIC-level BusLogic BT-958 11: 4670 4588 IO-APIC-level BusLogic BT-958 11: 4670 4588 IO-APIC-level BusLogic BT-958 11: 4670 4588 IO-APIC-level BusLogic BT-958 11: 4670 4588 IO-APIC-level BusLogic BT-958 11: 4670 4588 IO-APIC-level BusLogic BT-958 11: 4670 4588 IO-APIC-level BusLogic BT-958 11: 4670 4588 IO-APIC-level BusLogic BT-958 11: 4670 4588 IO-APIC-level BusLogic BT-958 Cheers, Dick Johnson Penguin : Linux version 2.4.18 on an i686 machine (797.90 BogoMips). The US military has given us many words, FUBAR, SNAFU, now ENRON. Yes, top management were graduates of West Point and Annapolis. - 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/