From owner-freebsd-fs@FreeBSD.ORG Wed Sep 9 10:44:02 2009 Return-Path: Delivered-To: freebsd-fs@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id BE03D1065696; Wed, 9 Sep 2009 10:44:02 +0000 (UTC) (envelope-from pjd@garage.freebsd.pl) Received: from mail.garage.freebsd.pl (chello087206049004.chello.pl [87.206.49.4]) by mx1.freebsd.org (Postfix) with ESMTP id 0D9028FC17; Wed, 9 Sep 2009 10:44:01 +0000 (UTC) Received: by mail.garage.freebsd.pl (Postfix, from userid 65534) id C008445CD9; Wed, 9 Sep 2009 12:43:59 +0200 (CEST) Received: from localhost (pdawidek.wheel.pl [10.0.1.1]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mail.garage.freebsd.pl (Postfix) with ESMTP id A205E45CA0; Wed, 9 Sep 2009 12:43:54 +0200 (CEST) Date: Wed, 9 Sep 2009 12:43:58 +0200 From: Pawel Jakub Dawidek To: Danny Carroll Message-ID: <20090909104358.GG1901@garage.freebsd.pl> References: <20090908172332.476d9e0b.gerrit@pmp.uni-hannover.de> <20090908164413.GC1539@garage.freebsd.pl> <20090909090715.9d8a58ef.gerrit@pmp.uni-hannover.de> <20090909083313.GA1901@garage.freebsd.pl> <4AA77834.1010007@dannysplace.net> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="ahP6B03r4gLOj5uD" Content-Disposition: inline In-Reply-To: <4AA77834.1010007@dannysplace.net> User-Agent: Mutt/1.4.2.3i X-PGP-Key-URL: http://people.freebsd.org/~pjd/pjd.asc X-OS: FreeBSD 8.0-CURRENT i386 X-Spam-Checker-Version: SpamAssassin 3.0.4 (2005-06-05) on mail.garage.freebsd.pl X-Spam-Level: X-Spam-Status: No, score=-5.9 required=4.5 tests=ALL_TRUSTED,BAYES_00 autolearn=ham version=3.0.4 Cc: freebsd-fs@freebsd.org, freebsd-stable@freebsd.org Subject: Re: zfs kernel panic X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 09 Sep 2009 10:44:02 -0000 --ahP6B03r4gLOj5uD Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Wed, Sep 09, 2009 at 07:41:08PM +1000, Danny Carroll wrote: > On 9/09/2009 6:33 PM, Pawel Jakub Dawidek wrote: > >On Wed, Sep 09, 2009 at 09:07:15AM +0200, Gerrit K=FChn wrote: > > =20 > >>On Tue, 8 Sep 2009 18:44:13 +0200 Pawel Jakub Dawidek > >>wrote about Re: zfs kernel panic: > >> > >>PJD> If this is amd64, add vm.kmem_size=3D"4G" to your loader.conf bac= k. > >> > >>What about vm.kmem_size_max? Does that also need tuning? > >> =20 > >No, this should be auto-tuned to some very large value. > > > > =20 > Pawel (et al), >=20 > Would it be possible for you to post to the list your ideas of a=20 > complete set of tuning parameters for ZFS on amd64? I have used the=20 > wiki article as a reference (http://wiki.freebsd.org/ZFSTuningGuide) but= =20 > it states that if you have > 2g ram and 7.2 then you do not need to tune= =20 > at all. I think that was the idea, although I see no reason to have less kernel address space than physical memory (except there might be other in-kernel variables auto-tuned based on kmem size). > I for one would be interested in learning a little more about how the=20 > memory should be tuned. Specifically what might be interesting is to=20 > know, once a parameter is set, is there an easy way to find out how it's= =20 > being used? i.e. If you start limiting the arc, is is possible to know=20 > what sort of hit/miss rate you are getting. There are ARC statistics available here: # sysctl kstat.zfs --=20 Pawel Jakub Dawidek http://www.wheel.pl pjd@FreeBSD.org http://www.FreeBSD.org FreeBSD committer Am I Evil? Yes, I Am! --ahP6B03r4gLOj5uD Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.4 (FreeBSD) iD8DBQFKp4buForvXbEpPzQRAoe2AKDFcQWjn0rVoeZSLczZmVM9BY5DEACg3whQ UK7cFH6qrKPIcHzdhAaRc7Q= =4+nt -----END PGP SIGNATURE----- --ahP6B03r4gLOj5uD--