Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751357AbWHCCUh (ORCPT ); Wed, 2 Aug 2006 22:20:37 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751362AbWHCCUh (ORCPT ); Wed, 2 Aug 2006 22:20:37 -0400 Received: from hu-out-0102.google.com ([72.14.214.193]:57394 "EHLO hu-out-0102.google.com") by vger.kernel.org with ESMTP id S1751357AbWHCCUg (ORCPT ); Wed, 2 Aug 2006 22:20:36 -0400 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=beta; d=gmail.com; h=received:message-id:date:from:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=OnOxUx4yXcZ8usw1CQ4oZYVv6VbBq3yDCfY8m7FxpRCki3rp6lU0UgGj1SrMUSIxCvR+2uh2mCYrLyqx2Qspjcg1BP3+xmpjs8m11GIvQ8gx8RD0HMOx9C0EQk119BdPDPmdunMSrdnVxWudp05FB+3tLi6uXqccJ/p5r6A0C3c= Message-ID: <7a329d910608021920h6c1bb625q5336115cfd253adf@mail.gmail.com> Date: Wed, 2 Aug 2006 19:20:25 -0700 From: "Wil Reichert" To: "Krzysztof Halasa" Subject: Re: Solaris ZFS on Linux Cc: "Kyle Moffett" , "Ian Stirling" , "David Masover" , "David Lang" , "Nate Diller" , "Adrian Ulrich" , "Horst H. von Brand" , ipso@snappymail.ca, lkml@lpbproductions.com, "Jeff Garzik" , "Theodore Ts'o" , "LKML Kernel" , reiserfs-list@namesys.com In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <20060731175958.1626513b.reiser4@blinkenlights.ch> <5c49b0ed0607311705t1eb8fc6bs9a68a43059bfa91a@mail.gmail.com> <20060801010215.GA24946@merlin.emma.line.org> <44CEAEF4.9070100@slaphack.com> <44CED95C.10709@slaphack.com> <44CFE8D9.9090606@mauve.plus.com> <0DA0B214-50BC-4E20-A520-B7AB121BB38B@mac.com> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1444 Lines: 30 On 8/2/06, Krzysztof Halasa wrote: > Kyle Moffett writes: > > > IMHO the best alternative for a situation like that is a storage > > controller with a battery-backed cache and a hunk of flash NVRAM for > > when the power shuts off (just in case you run out of battery), as > > well as a separate 1GB battery-backed PCI ramdisk for an external > > journal device (likewise equipped with flash NVRAM). It doesn't take > > much power at all to write a gig of stuff to a small flash chip > > (Think about your digital camera which runs off a couple AA's), so > > with a fair-sized on-board battery pack you could easily transfer its > > data to NVRAM and still have power left to back up data in RAM for 12 > > hours or so. That way bootup is fast (no reading 1GB of data from > > NVRAM) but there's no risk of data loss. > > Not sure - reading flash is fast, but writing is quite slow. > A digital camera can consume a set of 2 or 4 2500 mAh AA cells > for a fraction of 1 GB (of course, only a part of power goes > to flash). Seeks are fast, throughput is terrible, power is minimal: http://techreport.com/reviews/2006q3/supertalent-flashide/index.x?pg=1 Wil - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/