From owner-freebsd-stable@FreeBSD.ORG Tue Feb 28 15:08:16 2012 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 6CA571065670 for ; Tue, 28 Feb 2012 15:08:16 +0000 (UTC) (envelope-from paul@gromit.dlib.vt.edu) Received: from lennier.cc.vt.edu (lennier.cc.vt.edu [198.82.162.213]) by mx1.freebsd.org (Postfix) with ESMTP id 189178FC13 for ; Tue, 28 Feb 2012 15:08:15 +0000 (UTC) Received: from zidane.cc.vt.edu (zidane.cc.vt.edu [198.82.163.227]) by lennier.cc.vt.edu (8.13.8/8.13.8) with ESMTP id q1SEsk3s013078; Tue, 28 Feb 2012 09:54:46 -0500 Received: from auth3.smtp.vt.edu (EHLO auth3.smtp.vt.edu) ([198.82.161.152]) by zidane.cc.vt.edu (MOS 4.3.3-GA FastPath queued) with ESMTP id SEA47338; Tue, 28 Feb 2012 09:54:46 -0500 (EST) Received: from pmather.tower.lib.vt.edu (pmather.tower.lib.vt.edu [128.173.51.28]) (authenticated bits=0) by auth3.smtp.vt.edu (8.13.8/8.13.8) with ESMTP id q1SEsjhT004022 (version=TLSv1/SSLv3 cipher=AES128-SHA bits=128 verify=NO); Tue, 28 Feb 2012 09:54:46 -0500 Mime-Version: 1.0 (Apple Message framework v1084) Content-Type: text/plain; charset=us-ascii From: Paul Mather In-Reply-To: <4F4C53B6.6060909@norma.perm.ru> Date: Tue, 28 Feb 2012 09:54:45 -0500 Content-Transfer-Encoding: quoted-printable Message-Id: <93DCA53D-B71F-4B67-8CEF-CDECF3829C6D@gromit.dlib.vt.edu> References: <4F4B0F83.4090600@norma.perm.ru> <977febd5710ecac8cd9ea374ca0193f4.squirrel@109.169.62.232> <4F4C53B6.6060909@norma.perm.ru> To: "Eugene M. Zheganin" X-Mailer: Apple Mail (2.1084) X-Mirapoint-Received-SPF: 198.82.161.152 auth3.smtp.vt.edu paul@gromit.dlib.vt.edu 5 none X-Junkmail-Status: score=10/50, host=zidane.cc.vt.edu X-Junkmail-Signature-Raw: score=unknown, refid=str=0001.0A020203.4F4CEAB6.00A6,ss=1,re=0.000,fgs=0, ip=0.0.0.0, so=2011-07-25 19:15:43, dmn=2011-05-27 18:58:46, mode=single engine X-Junkmail-IWF: false Cc: freebsd-stable@freebsd.org Subject: Re: zfs, 1 gig of RAM and periodic weekly 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: Tue, 28 Feb 2012 15:08:16 -0000 On Feb 27, 2012, at 11:10 PM, Eugene M. Zheganin wrote: > Hi. >=20 > On 28.02.2012 01:02, Nenhum_de_Nos wrote: >> regardless of the pool size ? >>=20 >> I was planning on making an atom board a file server for my home, and = I have two options: soekris >> net6501 2GB RAM and intel board powered by the 330 atom (says 2GB = limited as well). My plans are >> to use from 4 up to 8 disks, and they should be 2TB at least. >>=20 >> As its for home use, some p2p software and mostly music listening and = sometimes movie streaming. >>=20 >> should 2GB be that bad, that I should drop it and use UFS instead ? >>=20 >> I may run any version of FreeBSD on it, was planning on 9-STABLE or = 9.1. >>=20 > In the same time I have a couple of hosts successfully running zfs on = 768 Megs and on 1 Gig of RAM. Both i386. > And they aren't affected by the periodic weekly for some reason. And = they are used only as fileservers. Basically the same story here: I am using a FreeBSD/i386 system with 768 = MB of RAM running RELENG_8 with 4 x 1 TB drives arranged as a RAIDZ1 = vdev. It is used as a Bacula server, backing up to the ZFS pool (with = ZFS compression enabled). It has been rock solid, and I've had no = problems with any of the periodic jobs. Here are the ZFS-related tunings I have in /boot/loader.conf: vm.kmem_size=3D"640M" vm.kmem_size_max=3D"640M" vfs.zfs.arc_max=3D"512M" vfs.zfs.txg.timeout=3D"5" If you are planning on using P2P a lot, I had heard that large files = fetched via Bittorrent can become very fragmented under ZFS (due to the = COW nature of ZFS and the way Bittorrent fetches files), especially if = the pool is very full, and so ZFS might not be the best thing to use if = you are also planning on streaming these files, especially on modest = hardware. UFS might be preferable in these circumstances. Cheers, Paul.