From owner-freebsd-questions@FreeBSD.ORG Wed Oct 1 10:05:09 2008 Return-Path: Delivered-To: freebsd-questions@FreeBSD.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id CFE7A106568F; Wed, 1 Oct 2008 10:05:09 +0000 (UTC) (envelope-from m.seaman@infracaninophile.co.uk) Received: from smtp.infracaninophile.co.uk (gate6.infracaninophile.co.uk [IPv6:2001:8b0:151:1::1]) by mx1.freebsd.org (Postfix) with ESMTP id 36B408FC1F; Wed, 1 Oct 2008 10:05:09 +0000 (UTC) (envelope-from m.seaman@infracaninophile.co.uk) Received: from lack-of-gravitas.thebunker.net (gateway.ash.thebunker.net [213.129.64.4]) (authenticated bits=0) by smtp.infracaninophile.co.uk (8.14.3/8.14.3) with ESMTP id m91A4xYd012315 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Wed, 1 Oct 2008 11:05:00 +0100 (BST) (envelope-from m.seaman@infracaninophile.co.uk) X-DKIM: Sendmail DKIM Filter v2.7.2 smtp.infracaninophile.co.uk m91A4xYd012315 DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=infracaninophile.co.uk; s=200708; t=1222855500; bh=vDnr1aEpcOH6Dn W9/rsK2i3JAW0+343P3IhO7s7SCUI=; h=Message-ID:Date:From:MIME-Version: To:CC:Subject:References:In-Reply-To:Content-Type: Content-Transfer-Encoding:Cc:Content-Type:Date:From:In-Reply-To: Message-ID:Mime-Version:References:To; z=Message-ID:=20<48E34B4A.3 060007@infracaninophile.co.uk>|Date:=20Wed,=2001=20Oct=202008=2011: 04:58=20+0100|From:=20Matthew=20Seaman=20|Organization:=20Infracaninophile|User-Agent:=20Thunderbird= 202.0.0.16=20(X11/20080811)|MIME-Version:=201.0|To:=20Jeremy=20Chad wick=20|CC:=20Wojciech=20Puchar=20,=20=0D=0A=20Danny=20Do=20, =0D=0A=20freebsd-questions@FreeBSD.org|Subject:=20Re:=20Optimal=20F ile=20System=20config=20for=202.5TB=20RAID5|References:=20=20<48E21C66.8080407@FreeBSD. org>=20=20<2008093016 1407.E16761@wojtek.tensor.gdynia.pl>=20=20<20080930205435.B20033@wojtek.tensor.gdynia.pl >=20<00ee01c92346$69508fa0$3bf1aee0$@com>=20<20080930224447.GA58065 @icarus.home.lan>=20<20081001083637.C7317@wojtek.tensor.gdynia.pl>= 20<48E33CC6.7050504@infracaninophile.co.uk>=20<20081001090832.GB159 39@icarus.home.lan>|In-Reply-To:=20<20081001090832.GB15939@icarus.h ome.lan>|X-Enigmail-Version:=200.95.6|Content-Type:=20text/plain=3B =20charset=3DUTF-8=3B=20format=3Dflowed|Content-Transfer-Encoding:= 207bit; b=WEITUG/CQ4Um50pdBLlLVWlp0OOqNNl+EhmXgutsEan08qRtAwhjeRuPO p/jwl4Jay/Uo0s1XOedlETFYN/yXb/T1unrby0lVkMTusAlYZKQqut/H1gUVPr30g9+ 6FM1CzoA02r42kkMdlsNv1IUAc++epepTDmzuTfYYWy7VSI= Message-ID: <48E34B4A.3060007@infracaninophile.co.uk> Date: Wed, 01 Oct 2008 11:04:58 +0100 From: Matthew Seaman Organization: Infracaninophile User-Agent: Thunderbird 2.0.0.16 (X11/20080811) MIME-Version: 1.0 To: Jeremy Chadwick References: <48E21C66.8080407@FreeBSD.org> <20080930161407.E16761@wojtek.tensor.gdynia.pl> <20080930205435.B20033@wojtek.tensor.gdynia.pl> <00ee01c92346$69508fa0$3bf1aee0$@com> <20080930224447.GA58065@icarus.home.lan> <20081001083637.C7317@wojtek.tensor.gdynia.pl> <48E33CC6.7050504@infracaninophile.co.uk> <20081001090832.GB15939@icarus.home.lan> In-Reply-To: <20081001090832.GB15939@icarus.home.lan> X-Enigmail-Version: 0.95.6 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.0 (smtp.infracaninophile.co.uk [81.187.76.162]); Wed, 01 Oct 2008 11:05:00 +0100 (BST) X-Virus-Scanned: ClamAV 0.94/8365/Wed Oct 1 10:03:36 2008 on happy-idiot-talk.infracaninophile.co.uk X-Virus-Status: Clean X-Spam-Status: No, score=-2.6 required=5.0 tests=AWL,BAYES_00,DKIM_SIGNED, DKIM_VERIFIED,SPF_FAIL autolearn=no version=3.2.5 X-Spam-Checker-Version: SpamAssassin 3.2.5 (2008-06-10) on happy-idiot-talk.infracaninophile.co.uk Cc: Wojciech Puchar , Danny Do , freebsd-questions@FreeBSD.org Subject: Re: Optimal File System config for 2.5TB RAID5 X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 01 Oct 2008 10:05:09 -0000 -----BEGIN PGP SIGNED MESSAGE----- Hash: RIPEMD160 Jeremy Chadwick wrote: | On Wed, Oct 01, 2008 at 10:03:02AM +0100, Matthew Seaman wrote: |> I've occasionally wondered why there isn't a simple device commonly available |> which consists of a few hundred MB of battery backed (or otherwise persistent |> in the face of power loss) RAM that can plug into a PCI slot and fulfil that |> function generically for any disks in a machine. Solid state hard drives are |> getting there, but they're still too expensive and not really fast enough yet. | | You mean this? | | http://en.wikipedia.org/wiki/I-RAM | Yeah -- pretty much that. Although I'd prefer something that doesn't try and pretend to be a hard drive -- after all, there's no reason to limit the thing to the performance envelope of a SATA bus. If you want solid state drives, nowadays there are devices based on compact flash that fit in a normal 3.5" drive bay, speak SATA and don't need standby power. Latency is much better than a normal HDD, but probably not so good as the I-RAM you pointed out. Cheers, Matthew - -- Dr Matthew J Seaman MA, D.Phil. Flat 3 ~ 7 Priory Courtyard PGP: http://www.infracaninophile.co.uk/pgpkey Ramsgate ~ Kent, CT11 9PW, UK -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.9 (FreeBSD) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iEYEAREDAAYFAkjjS0oACgkQ3jDkPpsZ+VaS5ACePK+3KUc+Kiu612I0JTqWJz9h WgoAmgNqC3/tNCmcfwogmFJZqs6gP4zF =nj5y -----END PGP SIGNATURE-----