Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932119AbWHBSNb (ORCPT ); Wed, 2 Aug 2006 14:13:31 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932122AbWHBSNb (ORCPT ); Wed, 2 Aug 2006 14:13:31 -0400 Received: from ptb-relay03.plus.net ([212.159.14.214]:48257 "EHLO ptb-relay03.plus.net") by vger.kernel.org with ESMTP id S932119AbWHBSNb (ORCPT ); Wed, 2 Aug 2006 14:13:31 -0400 Message-ID: <44D0EB07.4040007@mauve.plus.com> Date: Wed, 02 Aug 2006 19:12:23 +0100 From: Ian Stirling User-Agent: Mozilla Thunderbird 1.0 (X11/20041206) X-Accept-Language: en-us, en MIME-Version: 1.0 To: Krzysztof Halasa CC: Kyle Moffett , 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 Subject: Re: Solaris ZFS on Linux References: <20060731175958.1626513b.reiser4@blinkenlights.ch> <200607311918.k6VJIqTN011066@laptop13.inf.utfsm.cl> <20060731225734.ecf5eb4d.reiser4@blinkenlights.ch> <44CE7C31.5090402@gmx.de> <5c49b0ed0607311621i54f1c46fh9137f8955c9ea4be@mail.gmail.com> <5c49b0ed0607311650j4b86d0c3h853578f58db16140@mail.gmail.com> <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> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1344 Lines: 29 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 > 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). Yeah - that's why I said in the original message that it's not especially lower in energy - the energy is used at a lower rate, so is much cheaper to supply. http://www.samsung.com/products/semiconductor/NORFlash/256Mbit/K8A5615EBA/K8A5615EBA.htm 's datasheet says to program the 32Mbyte chip takes about 30mw*120s, or 3.5J or so. For a gigabyte, that's 100J - a fairly substantial amount of energy. However - it's at a low rate, so it's not _too_ expensive to supply. - 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/