From owner-freebsd-current@FreeBSD.ORG Mon Dec 28 08:21:31 2009 Return-Path: Delivered-To: freebsd-current@FreeBSD.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 821CA106568B for ; Mon, 28 Dec 2009 08:21:31 +0000 (UTC) (envelope-from Johan@double-l.nl) Received: from smtp-vbr15.xs4all.nl (smtp-vbr15.xs4all.nl [194.109.24.35]) by mx1.freebsd.org (Postfix) with ESMTP id 028FA8FC1B for ; Mon, 28 Dec 2009 08:21:30 +0000 (UTC) Received: from w2003s01.double-l.local (double-l.xs4all.nl [80.126.205.144]) by smtp-vbr15.xs4all.nl (8.13.8/8.13.8) with ESMTP id nBS8LCQk099336; Mon, 28 Dec 2009 09:21:17 +0100 (CET) (envelope-from Johan@double-l.nl) Content-class: urn:content-classes:message MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable X-MimeOLE: Produced By Microsoft Exchange V6.5 Date: Mon, 28 Dec 2009 09:21:11 +0100 Message-ID: <57200BF94E69E54880C9BB1AF714BBCBA573F9@w2003s01.double-l.local> X-MS-Has-Attach: X-MS-TNEF-Correlator: Thread-Topic: 8.0-RELEASE: disk IO temporarily hangs up (ZFS or ATA relatedproblem) Thread-Index: AcqEEIB3T3lu5OksRIGX0TVwPPZWQwDhe3HQ References: <39309F560B98453EBB9AEA0F29D9D80E@vosz.local><3bbf2fe10912181004w2a1abff2re8f77fd6a8bc3233@mail.gmail.com> From: "Johan Hendriks" To: "David P. Discher" X-Virus-Scanned: by XS4ALL Virus Scanner Cc: freebsd-current@FreeBSD.org Subject: RE: 8.0-RELEASE: disk IO temporarily hangs up (ZFS or ATA relatedproblem) 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: Mon, 28 Dec 2009 08:21:31 -0000 > >ZFS will write buffer ALOT. Your settings of vfs.zfs.arc_min and vfs.zfs.arc_max will likely affect how bursty this >is. I've been running with Min, 32 GB arc, and see very bursty writes (of course, my systems have 64GB).=20 >Also, use 'zpool iostat 1' and not the system iostat. Check gstat as well. >also try using CAM_ATA (ahci.ko) instead of ad devices, so your can get the benefits of tag queuing. >There is also a possible undocumented issue with, I believe it was the WD green drives, where the vibration of the >drive actually slowed it down. This was demonstrated by setting a pound or two of silly putty on the top of the >drive, and its performance (significantly) increased. Experiment with putting some heavily, non-conductive weight on >top of each drive - a book or something.=20 Even with hardware the FreeBSD Handbook comes Handy ;-)=20 > ensure that is its securely mounted as well.=20 >--- >David P. Discher >dpd@bitgravity.com * AIM: bgDavidDPD >BITGRAVITY * http://www.bitgravity.com >On Dec 18, 2009, at 12:04 PM, Alexander Zagrebin wrote: >>>> The disks are used for mirrored ZFS pool. >>>> I have noticed that the system periodically locks up on=20 >>> disk operations. >>>> After approx. 10 min of very slow disk i/o (several KB/s)=20 >>> the speed of disk >>>> operations restores to normal. >>>> gstat has shown that the problem is in ad6. >>>=20 >>> Want you try this patch and report?: >>> http://people.freebsd.org/~attilio/lockmgr_lostwake.diff >>>=20 >>> It should apply to STABLE_8 and if not, just report and I will help. >>=20 >> Thanks fo your attempt to help! >> I've successfully applied this patch to RELENG_8_0, recompiled >> kernel and required modules (krpc, opensolaris,zfs), >> but nothing has changed. The problem still exist. >>=20 >> --=20 >> Alexander Zagrebin >>=20 >> _______________________________________________ >> freebsd-current@freebsd.org mailing list >> http://lists.freebsd.org/mailman/listinfo/freebsd-current >> To unsubscribe, send any mail to "freebsd-current-unsubscribe@freebsd.org"