From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Sat, 30 Jun 2007 06:02:44 -0400 Message-ID: <87bqexiwu3.wl%peter@chubb.wattle.id.au> From: peter@chubb.wattle.id.au In-Reply-To: <20070630093243.GD22354@infradead.org> References: <20070624042345.GB20033@wotan.suse.de> <6934efce0706251708h7ab8d7dal6682def601a82073@mail.gmail.com> <20070626060528.GA15134@infradead.org> <6934efce0706261007x5e402eebvc528d2d39abd03a3@mail.gmail.com> <20070630093243.GD22354@infradead.org> MIME-Version: 1.0 (generated by SEMI 1.14.6 - "Maruoka") Subject: Re: vm/fs meetup in september? Content-Type: text/plain; charset=US-ASCII Sender: owner-linux-mm@kvack.org Return-Path: To: Christoph Hellwig , Jared Hulbert , Nick Piggin , Linux Kernel Mailing List , Linux Memory Management List , linux-fsdevel@vger.kernel.org List-ID: >>>>> "Christoph" == Christoph Hellwig writes: Christoph> On Tue, Jun 26, 2007 at 10:07:24AM -0700, Jared Hulbert Christoph> wrote: >> If you have a large array of a non-volatile semi-writeable memory >> such as a highspeed NOR Flash or some of the similar emerging >> technologies in a system. It would be useful to use that memory as >> an extension of RAM. One of the ways you could do that is allow >> pages to be swapped out to this memory. Once there these pages >> could be read directly, but would require a COW procedure on a >> write access. The reason why I think this may be a vm/fs topic is >> that the hardware makes writing to this memory efficiently a >> non-trivial operation that requires management just like a >> filesystem. Also it seems to me that there are probably overlaps >> between this topic and the recent filemap_xip.c discussions. Christoph> So what you mean is "swap on flash" ? Defintively sounds Christoph> like an interesting topic, although I'm not too sure it's Christoph> all that filesystem-related. You need either a block translation layer, or a (swap) filesystem that understands flash peculiarities in order to make such a thing work. The standard Linux swap format will not work. -- Dr Peter Chubb http://www.gelato.unsw.edu.au peterc AT gelato.unsw.edu.au http://www.ertos.nicta.com.au ERTOS within National ICT Australia -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org