From mboxrd@z Thu Jan 1 00:00:00 1970 From: Hans Reiser Subject: Re: reiser4 and laptop_mode Date: Mon, 17 Oct 2005 19:28:31 -0700 Message-ID: <43545DCF.1070301@namesys.com> References: <19812996093.20051017162429@usu.ru> <43542DE1.7050700@slaphack.com> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: list-help: list-unsubscribe: list-post: Errors-To: flx@namesys.com In-Reply-To: <43542DE1.7050700@slaphack.com> List-Id: Content-Type: text/plain; charset="us-ascii" To: David Masover Cc: Sinitsyn Valentine , reiserfs-list@namesys.com, Alexander Zarochentcev David Masover wrote: >Sinitsyn Valentine wrote: > > >>Hi all, >> >>I'm considering installing Reiser4 on my laptop, but I also want to >>use laptop_mode (http://www.xs4all.nl/~bsamwel/laptop_mode/index.html) >>to save battery power. So I'm wondering wether these two products are >>compatible with each other? I know that Reiser3 and ext3 did require >>special patches (now included in mainstream kernels) which schedule >>commits in a way which allows hard drive to spin down. I've looked >>through Google and this mailing list but didn't find any references to >>similar patches for Reiser4. Are they needed but nobody wrote them yet >>or is Reiser4 spindown-friendly just out of the box? >> >> > >Reiser4 is spindown-friendly in one way -- until you run out of RAM, it >won't commit. > This is not true (it would need to be fixed if it was). You can adjust how frequent commits are if you don't like our kernel compilation optimized defaults. > In fact, if you have enough RAM, you won't ever touch the >disk -- deleting a file before it's committed means it never touches disk. > >It is not as spindown-friendly as laptop_mode, which notices when the >drive has to spin up anyway (maybe through a read) and flushes all >writes. Don't know if they are compatible. > > We should work to integrate well with it. Zam, can you look at that? Thanks. > > >