From owner-freebsd-arm@FreeBSD.ORG Mon Mar 23 07:42:00 2015 Return-Path: Delivered-To: freebsd-arm@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id 0750172E for ; Mon, 23 Mar 2015 07:42:00 +0000 (UTC) Received: from wa3yre.wynn.com (wa3yre.wynn.com [199.89.147.3]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 8B21CD0F for ; Mon, 23 Mar 2015 07:41:59 +0000 (UTC) Received: from ivory.wynn.com (mail.wynn.com [199.89.147.3]) (authenticated bits=0) by wa3yre.wynn.com (8.14.3/8.12.6) with ESMTP id t2N7fmCh034867; Mon, 23 Mar 2015 03:41:49 -0400 (EDT) (envelope-from freebsd-arm@wynn.com) Date: Mon, 23 Mar 2015 03:41:47 -0400 From: Brett Wynkoop To: Peter Jeremy Subject: Re: ZFS on RPi (was: zfs on BeagleBone) Message-ID: <20150323034147.476a6f3f@ivory.wynn.com> In-Reply-To: <20150321065346.GA64358@server.rulingia.com> References: <20150311130932.3493a938@ivory.wynn.com> <20150321065346.GA64358@server.rulingia.com> X-Mailer: Claws Mail 3.10.1 (GTK+ 2.24.25; x86_64-apple-darwin10.8.0) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Cc: freebsd-arm@freebsd.org X-BeenThere: freebsd-arm@freebsd.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: "Porting FreeBSD to ARM processors." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 23 Mar 2015 07:42:00 -0000 On Sat, 21 Mar 2015 17:53:46 +1100 Peter Jeremy wrote: > panic: vm_fault: fault on nofault entry, addr: dd2f1000 > KDB: stack backtrace: > Uptime: 11m46s > Physical memory: 473 MB > Dumping 36 MB:sdhci_bcm0: DMA in use > > The tuning I did was: > vfs.zfs.arc_max="24M" > vfs.zfs.vdev.cache.size="5M" > Sorry for the delay. Other things have kept me from being as attentive to the arm list as I might like. It seems you did not tune vm.kmem_size. In my experience with smallish systems running FreeBSD with zfs that is mandatory. My 256M BBone has this: vm.kmem_size="256M" vm.kmem_size_max="256M" #vfs.zfs.arc_max="40M" #vfs.zfs.arc_max="64M" vfs.zfs.arc_max="24M" vfs.zfs.vdev.cache.size="5M" I strongly suggest setting vm.kmem_size to your real memory and do the same with vm.kmem_size_max. I came up with this after doing loads of reading for zfs on memory restricted systems. Remember by default zfs really wants at least 1GB main memory, and that is still tight, most references claim 2GB is the practical lower limit on x86. I have it running on an x86 box with 512MB, but could not make it run on 384MB on FreeBSD x86. -Brett -- wynkoop@wynn.com http://prd4.wynn.com/wynkoop/pgp-keys.txt 917-642-6925 929-272-0000 If cowardly and dishonorable men sometimes shoot unarmed men with army pistols or guns, the evil must be prevented by the penitentiary and gallows, and not by a general deprivation of a constitutional privilege. -Honorable J. A. Williams, Circuit Judge - Wilson v. State, 33 Ark. 557, 34 Am. Rep. 52 (1878).