From owner-freebsd-current@FreeBSD.ORG Sat Sep 3 22:38:14 2005 Return-Path: X-Original-To: current@freebsd.org Delivered-To: freebsd-current@FreeBSD.ORG Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 05F9616A41F for ; Sat, 3 Sep 2005 22:38:14 +0000 (GMT) (envelope-from benlutz@datacomm.ch) Received: from maxlor.mine.nu (c-213-160-32-54.customer.ggaweb.ch [213.160.32.54]) by mx1.FreeBSD.org (Postfix) with ESMTP id 05D9B43D48 for ; Sat, 3 Sep 2005 22:38:12 +0000 (GMT) (envelope-from benlutz@datacomm.ch) Received: from localhost (localhost [127.0.0.1]) by maxlor.mine.nu (Postfix) with ESMTP id F33B94F0 for ; Sun, 4 Sep 2005 00:42:51 +0200 (CEST) Received: from maxlor.mine.nu ([127.0.0.1]) by localhost (midgard.intranet [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 38478-02 for ; Sun, 4 Sep 2005 00:42:50 +0200 (CEST) Received: from [10.0.0.23] (mini.intranet [10.0.0.23]) by maxlor.mine.nu (Postfix) with ESMTP id 6C82C190 for ; Sun, 4 Sep 2005 00:42:50 +0200 (CEST) Message-ID: <431A25CB.8050503@datacomm.ch> Date: Sun, 04 Sep 2005 00:38:03 +0200 From: Benjamin Lutz User-Agent: Mozilla Thunderbird 1.0.6 (Macintosh/20050716) X-Accept-Language: en-us, en MIME-Version: 1.0 To: FreeBSD-Current X-Enigmail-Version: 0.92.0.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="------------enigF87B48B842847D74CC9623D1" X-Virus-Scanned: amavisd-new at maxlor.mine.nu X-Content-Filtered-By: Mailman/MimeDel 2.1.5 Cc: Subject: Very slow disk writes because of wdrain X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 03 Sep 2005 22:38:14 -0000 This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enigF87B48B842847D74CC9623D1 Content-Type: multipart/mixed; boundary="------------070801050104030503010500" This is a multi-part message in MIME format. --------------070801050104030503010500 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Hello, I've upgraded a Server of mine to FreeBSD-6.0-BETA3 today (fresh install), and I've run into a problem. Writes to the disk are extremely slow, eg: $ dd if=/dev/zero of=/usr/test bs=1048576 count=100 100+0 records in 100+0 records out 104857600 bytes transferred in 13.771165 secs (7614287 bytes/sec) $ During the write, dd spends pretty much all it's time in the wdrain state, CPU usage is about 5% (this is a Pentium 4 2.4GHz). Reading from the disk (as far as I can tell by dd'ing stuff to /dev/null) is as fast as it's supposed to be. wdrain is defined in /usr/src/sys/kern/vfs_bio.c:384. A posting to questions in march last year recommends increasing vfs.hirunningspace (default: 1M) to 4M. This has no impact however on the speed, nor does increasing it to 16M. The disk in question is a SCSI RAID 1 array, which has been working very well under FreeBSD 4.11 before. I'm running a custom kernel with the debugging options as well as the hardware I don't use removed. Please see the attached dmesg.txt and kernel.txt for details. Now, I'd like to get fast speeds again from this machine, can anyone help me? Thanks, Benjamin --------------070801050104030503010500-- --------------enigF87B48B842847D74CC9623D1 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.0 (Darwin) iD8DBQFDGiXRgShs4qbRdeQRAsJbAJ9sAojdcTEaN/sL4RwFiGYX0t4vPwCggZnp Ged9TKv4L68XYb4M2gGoK3c= =Cpir -----END PGP SIGNATURE----- --------------enigF87B48B842847D74CC9623D1--