Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750884AbWHBO2Z (ORCPT ); Wed, 2 Aug 2006 10:28:25 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750882AbWHBO2Z (ORCPT ); Wed, 2 Aug 2006 10:28:25 -0400 Received: from khc.piap.pl ([195.187.100.11]:20884 "EHLO khc.piap.pl") by vger.kernel.org with ESMTP id S1750771AbWHBO2Y (ORCPT ); Wed, 2 Aug 2006 10:28:24 -0400 To: Kyle Moffett Cc: 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 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> From: Krzysztof Halasa Date: Wed, 02 Aug 2006 16:28:20 +0200 In-Reply-To: <0DA0B214-50BC-4E20-A520-B7AB121BB38B@mac.com> (Kyle Moffett's message of "Tue, 1 Aug 2006 22:29:20 -0400") Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1244 Lines: 25 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). -- Krzysztof Halasa - 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/