From owner-freebsd-performance@FreeBSD.ORG Mon May 2 22:28:57 2005 Return-Path: Delivered-To: freebsd-performance@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id B30E016A4D0 for ; Mon, 2 May 2005 22:28:57 +0000 (GMT) Received: from smtp818.mail.sc5.yahoo.com (smtp818.mail.sc5.yahoo.com [66.163.170.4]) by mx1.FreeBSD.org (Postfix) with SMTP id EE28243D6E for ; Mon, 2 May 2005 22:28:56 +0000 (GMT) (envelope-from noackjr@alumni.rice.edu) Received: from unknown (HELO optimator.noacks.org) (noacks@swbell.net@70.240.205.64 with login) by smtp818.mail.sc5.yahoo.com with SMTP; 2 May 2005 22:16:55 -0000 Received: from localhost (localhost [127.0.0.1]) by optimator.noacks.org (Postfix) with ESMTP id 5BED7610A; Mon, 2 May 2005 17:16:54 -0500 (CDT) Received: from optimator.noacks.org ([127.0.0.1]) by localhost (optimator.noacks.org [127.0.0.1]) (amavisd-new, port 10024) with LMTP id 08669-04; Mon, 2 May 2005 17:16:50 -0500 (CDT) Received: from [127.0.0.1] (optimator [192.168.1.11]) by optimator.noacks.org (Postfix) with ESMTP id 3DF0960D2; Mon, 2 May 2005 17:16:50 -0500 (CDT) Message-ID: <4276A6CC.3000108@alumni.rice.edu> Date: Mon, 02 May 2005 17:16:44 -0500 From: Jonathan Noack User-Agent: Mozilla Thunderbird 1.0.2 (Windows/20050317) X-Accept-Language: en-us, en MIME-Version: 1.0 To: Steven Hartland References: <19879.1115061648@critter.freebsd.dk> <00fe01c54f61$df220d60$b3db87d4@multiplay.co.uk> In-Reply-To: <00fe01c54f61$df220d60$b3db87d4@multiplay.co.uk> X-Enigmail-Version: 0.91.0.0 OpenPGP: id=991D8195; url=http://www.noacks.org/cert/noackjr.asc Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="------------enigDA032C7B1FAEFCCE124B0366" X-Virus-Scanned: amavisd-new at noacks.org cc: Eric Anderson cc: Poul-Henning Kamp cc: Robert Watson cc: freebsd-performance@freebsd.org Subject: Re: Very low disk performance on 5.x X-BeenThere: freebsd-performance@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list Reply-To: noackjr@alumni.rice.edu List-Id: Performance/tuning List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 02 May 2005 22:28:57 -0000 This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enigDA032C7B1FAEFCCE124B0366 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit On 5/2/2005 4:56 PM, Steven Hartland wrote: > ----- Original Message ----- From: "Poul-Henning Kamp" >> On -current and 5.4 you don't have to make partitions if you >> intend to use the entire disk (and provided you don't want >> to boot from it). You can simply: >> >> newfs /dev/da0 >> mount /dev/da0 /where_ever > > /dev/da0: 1526216.3MB (3125691008 sectors) block size 16384, fragment > size 2048 > using 8306 cylinder groups of 183.77MB, 11761 blks, 23552 inodes. > mount /dev/da0 /mnt > > dd if=/dev/zero of=/mnt/testfile bs=64k count=100000 > 100000+0 records in > 100000+0 records out > 6553600000 bytes transferred in 44.424588 secs (147521908 bytes/sec) > > /usr/bin/time -h dd of=/dev/null if=/mnt/testfile bs=64k > count=100000 100000+0 records in > 100000+0 records out > 6553600000 bytes transferred in 48.150473 secs (136106658 bytes/sec) > 48.27s real 0.01s user 12.33s sys > > /usr/bin/time -h cat /mnt/testfile > /dev/null > 48.12s real 0.26s user 14.92s sys > > Raw read: > /usr/bin/time -h dd of=/dev/null if=/dev/da0 bs=64k > count=100000 100000+0 records in > 100000+0 records out > 6553600000 bytes transferred in 32.028544 secs (204617482 bytes/sec) > 32.02s real 0.02s user 2.73s sys Look at the difference in sys times for raw vs. filesystem reads. With raw we're at 2.73s while reading from the filesystem requires 12.33s! From my position of complete ignorance that seems like a lot... -- Jonathan Noack | noackjr@alumni.rice.edu | OpenPGP: 0x991D8195 --------------enigDA032C7B1FAEFCCE124B0366 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.1 (MingW32) iD8DBQFCdqbQUFz01pkdgZURAs7XAJ4oZksFCPBuH65I30UylE+HZhCJHgCeOXpw E6YXzImxHepv1kqpyHPwDz8= =XBU1 -----END PGP SIGNATURE----- --------------enigDA032C7B1FAEFCCE124B0366--