From owner-freebsd-stable@FreeBSD.ORG Thu Jan 20 18:48:47 2005 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 54ECA16A4CE for ; Thu, 20 Jan 2005 18:48:47 +0000 (GMT) Received: from mail.gmx.net (mail.gmx.de [213.165.64.20]) by mx1.FreeBSD.org (Postfix) with SMTP id 4538D43D2D for ; Thu, 20 Jan 2005 18:48:46 +0000 (GMT) (envelope-from emanuel.strobl@gmx.net) Received: (qmail invoked by alias); 20 Jan 2005 18:48:44 -0000 Received: from flb.schmalzbauer.de (EHLO cale.flintsbach.schmalzbauer.de) (62.245.232.135) by mail.gmx.net (mp012) with SMTP; 20 Jan 2005 19:48:44 +0100 X-Authenticated: #301138 From: Emanuel Strobl To: freebsd-stable@freebsd.org Date: Thu, 20 Jan 2005 19:48:38 +0100 User-Agent: KMail/1.7.2 X-Birthday: 10/06/72 X-CelPhone: +49 173 9967781 X-Tel: +49 89 18947781 X-Country: Germany X-Address: Munich, 80686 X-OS: FreeBSD MIME-Version: 1.0 Content-Type: multipart/signed; boundary="nextPart2359445.XJB2V7ZaMH"; protocol="application/pgp-signature"; micalg=pgp-sha1 Content-Transfer-Encoding: 7bit Message-Id: <200501201948.42707.emanuel.strobl@gmx.net> X-Y-GMX-Trusted: 0 Subject: Higher ATA-Mode -> lower speed X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 20 Jan 2005 18:48:47 -0000 --nextPart2359445.XJB2V7ZaMH Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable Content-Disposition: inline Dear ata interested guys, I observed a strange behaviour which seems to explain my often noticed "16M= B/s=20 hard-limit" I have a UDMA133 drive (MAXTOR 6L060J3) which saturates at 16MB/s when I du= mp=20 anything to it, regardless of the block size. This transfer rate is reached= =20 with bs=3D4k and doesn't increase any more even not with bs=3D64k. Now, when I set the mode to UDMA100 I get well over 40MB/s!!!! Can anybody confirm that for different hw? Especially people like fandino w= ho=20 already discussed poor ata performance on -current (~16 Oct. 04). Why does UDMA133 mode limit the transfer speed so badly? And why do I get=20 significantly slower transfer rates (32MB/s insted of 42MB/s) when I set th= e=20 mode to UDMA66 (compared to UDMA100 but twice the speed of UDMA133)? There'= s=20 only one device on the channel, so UDMA66 should be fine for 42MB/s. The controller is a HPT372. Best regards, =2DHarry --nextPart2359445.XJB2V7ZaMH Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.0 (FreeBSD) iD8DBQBB7/0KBylq0S4AzzwRAlXlAKCLCXNUVkjXQmNWDV4Hd/kOg4dNGQCfW9LK uuUs0LRqrsuhqlS4qEseVU8= =T5QT -----END PGP SIGNATURE----- --nextPart2359445.XJB2V7ZaMH--