Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S275335AbTHSFDq (ORCPT ); Tue, 19 Aug 2003 01:03:46 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S275340AbTHSFDq (ORCPT ); Tue, 19 Aug 2003 01:03:46 -0400 Received: from h80ad2781.async.vt.edu ([128.173.39.129]:43649 "EHLO turing-police.cc.vt.edu") by vger.kernel.org with ESMTP id S275335AbTHSFDp (ORCPT ); Tue, 19 Aug 2003 01:03:45 -0400 Message-Id: <200308190503.h7J53dVq004714@turing-police.cc.vt.edu> X-Mailer: exmh version 2.6.3 04/04/2003 with nmh-1.0.4+dev To: "Nayak, Samdeep" Cc: linux-kernel@vger.kernel.org Subject: Re: Linux SCSI benchmarking tool?? In-Reply-To: Your message of "Mon, 18 Aug 2003 21:52:54 PDT." From: Valdis.Kletnieks@vt.edu References: Mime-Version: 1.0 Content-Type: multipart/signed; boundary="==_Exmh_463093572P"; micalg=pgp-sha1; protocol="application/pgp-signature" Content-Transfer-Encoding: 7bit Date: Tue, 19 Aug 2003 01:03:38 -0400 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1788 Lines: 41 --==_Exmh_463093572P Content-Type: text/plain; charset=us-ascii On Mon, 18 Aug 2003 21:52:54 PDT, "Nayak, Samdeep" said: > have used dd, dt, IOmeter and rawio utilities so far and each seemed to > represent a different picture to me on the same setup (Single target with > few LUNS). (DD showed good performance on an ext2 mounted file system till > I realized that I was writing to the buffer and not writing on the raw > drive). Since I am trying to catch up with the SCSI world, I am just > wondering if any one else has tried any other utilities that would provide > better results or am I doing something wrong here?? Those tools report different things because they are measuring different aspects of the performance. For many system configurations, the fact that 'dd' is writing on a buffer rather than a drive is actually a *feature*, as you might care about just how much of a boost the cache is giving you - I don't care how fast my compile writes to disk, I care how fast the cache and page subsystems actually present the data to userspace... "better results" depends on the question - otherwise "42" is as good an answer as any, for exactly the reasons that Deep Thought gave.... ;) --==_Exmh_463093572P Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.2.2 (GNU/Linux) Comment: Exmh version 2.5 07/13/2001 iD8DBQE/Qa+qcC3lWbTT17ARAuWQAKCNCOW4dp9xWKvCRmUAGn6Uloo5CgCfXOGW qlUfVyEXcDJtBbm8tKfpjjg= =UBGw -----END PGP SIGNATURE----- --==_Exmh_463093572P-- - 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/