From owner-freebsd-stable@FreeBSD.ORG Mon Sep 1 10:53:00 2008 Return-Path: Delivered-To: stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 5280D106567E for ; Mon, 1 Sep 2008 10:53:00 +0000 (UTC) (envelope-from jdc@koitsu.dyndns.org) Received: from QMTA07.westchester.pa.mail.comcast.net (qmta07.westchester.pa.mail.comcast.net [76.96.62.64]) by mx1.freebsd.org (Postfix) with ESMTP id F2F008FC20 for ; Mon, 1 Sep 2008 10:52:59 +0000 (UTC) (envelope-from jdc@koitsu.dyndns.org) Received: from OMTA03.westchester.pa.mail.comcast.net ([76.96.62.27]) by QMTA07.westchester.pa.mail.comcast.net with comcast id 9Nld1a0080bG4ec57Nsz8h; Mon, 01 Sep 2008 10:52:59 +0000 Received: from koitsu.dyndns.org ([67.180.253.227]) by OMTA03.westchester.pa.mail.comcast.net with comcast id 9Nsx1a0014v8bD73PNsy4J; Mon, 01 Sep 2008 10:52:59 +0000 X-Authority-Analysis: v=1.0 c=1 a=6CuBM159f7AA:10 a=o7YMFg7W_UYA:10 a=QycZ5dHgAAAA:8 a=KJNmFWdNJKcRUTKvkEwA:9 a=l4yxoDvlQWRv8TfcTGYA:7 a=_5FwpDf2gG27SujkWOt7PKtYL64A:4 a=EoioJ0NPDVgA:10 a=LY0hPdMaydYA:10 Received: by icarus.home.lan (Postfix, from userid 1000) id B874B17B84E; Mon, 1 Sep 2008 03:52:57 -0700 (PDT) Date: Mon, 1 Sep 2008 03:52:57 -0700 From: Jeremy Chadwick To: Wes Morgan Message-ID: <20080901105257.GA4269@icarus.home.lan> References: <20080901021528.GB56694@what-creek.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.18 (2008-05-17) Cc: stable@freebsd.org, John Birrell Subject: Re: ZFS performance issues (solved?!) X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 01 Sep 2008 10:53:00 -0000 On Mon, Sep 01, 2008 at 05:48:34AM -0500, Wes Morgan wrote: > On Mon, 1 Sep 2008, John Birrell wrote: > >> For those people experiencing a performance degradation since the >> DTrace import, please update your copy of >> src/sys/cddl/compat/opensolaris/kern/opensolaris_kmem.c by either cvsup >> of direct edit to remove "#define KMEM_DEBUG". >> >> You only need to rebuild the opensolaris kernel module after this >> change. The code is shared between ZFS and DTrace via the opensolaris >> kernel module. >> >> This is also the reason why you found it necessary to add KDB, DDB and >> STACK to your kernel. After removing KMEM_DEBUG, you won't need those. >> >> Please confirm that this solves the problem you have been seeing. > > 8 or so hours later and everything is good here. > > One other suggestion, the "opensolaris" module that is now required for > zfs is not mentioned anywhere in UPDATING. Users of "MODULES_OVERRIDE" > will likely find themselves with a system that will not boot without > manual intervention, sometimes even requiring a live cd. A headsup or > warning would probably be appreciated by other zfs'ers. I second this motion. Upon rebuilding my system this morning, I was surprised to see the kernel printf()s about OpenSolaris and CDDL, and could find no mention of what purpose the module served. I'm assuming it's a module with some centralised code-pieces that DTrace and ZFS share, but I don't have any confirmation of this. -- | Jeremy Chadwick jdc at parodius.com | | Parodius Networking http://www.parodius.com/ | | UNIX Systems Administrator Mountain View, CA, USA | | Making life hard for others since 1977. PGP: 4BD6C0CB |