Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750975AbXAPS7M (ORCPT ); Tue, 16 Jan 2007 13:59:12 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751051AbXAPS7K (ORCPT ); Tue, 16 Jan 2007 13:59:10 -0500 Received: from mail.tmr.com ([64.65.253.246]:45966 "EHLO gaimboi.tmr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750906AbXAPS7G (ORCPT ); Tue, 16 Jan 2007 13:59:06 -0500 Message-ID: <45AD2100.9030900@tmr.com> Date: Tue, 16 Jan 2007 14:01:20 -0500 From: Bill Davidsen Organization: TMR Associates Inc, Schenectady NY User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.8.0.8) Gecko/20061105 SeaMonkey/1.0.6 MIME-Version: 1.0 To: Linux Portal , Linux Kernel mailing List Subject: Re: Simple utility to measure disk random access time References: In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1697 Lines: 53 Linux Portal wrote: > And a few graphs here: http://linux.inet.hr/how_fast_is_your_disk.html > > Comments welcome! These results: gaimboi:davidsen> ./da /dev/hdb Seeker v2.0, 2007-01-15, http://linux.inet.hr/how_fast_is_your_disk.html Benchmarking /dev/hdb [0MB], wait 30 seconds.............................. Results: 565841 seeks/second, 0.00 ms random access time gaimboi:davidsen> ./da /dev/hda Seeker v2.0, 2007-01-15, http://linux.inet.hr/how_fast_is_your_disk.html Benchmarking /dev/hda [19092MB], wait 30 seconds.............................. Results: 49 seeks/second, 20.20 ms random access time gaimboi:davidsen> ./da /dev/hdc Seeker v2.0, 2007-01-15, http://linux.inet.hr/how_fast_is_your_disk.html Benchmarking /dev/hdc [57241MB], wait 30 seconds.............................. Results: 64 seeks/second, 15.56 ms random access time led to this patch: RCS file: RCS/disk_access.c,v retrieving revision 1.1 diff -r1.1 disk_access.c 67a68,72 > if (numblocks <= 0) { > /* pretty small disk found here */ > printf("Disk too small, size: %d blocks\n", numblocks); > exit(EXIT_FAILURE); > } 69a75 > and this warning: gaimboi:davidsen> ./da /dev/hdb Seeker v2.0, 2007-01-15, http://linux.inet.hr/how_fast_is_your_disk.html Disk too small, size: 0 blocks -- bill davidsen CTO TMR Associates, Inc Doing interesting things with small computers since 1979 - 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/