From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from frost.carfax.org.uk ([85.119.82.111]:36998 "EHLO frost.carfax.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755561AbaAVNfd (ORCPT ); Wed, 22 Jan 2014 08:35:33 -0500 Date: Wed, 22 Jan 2014 13:35:08 +0000 From: Hugo Mills To: dsterba@suse.cz, Toggenburger Lukas , Tomasz Torcz , "linux-btrfs@vger.kernel.org" Subject: Re: Working on Btrfs as topic for master thesis Message-ID: <20140122133508.GH3314@carfax.org.uk> References: <8E968DF3B7EC0D40B67B5A9D25675A6A03FC70@MBXSRV03EDU.edu.local> <20140117160436.GA3356@mother.pipebreaker.pl> <8E968DF3B7EC0D40B67B5A9D25675A6A0400BF@MBXSRV03EDU.edu.local> <20140122120533.GE6498@twin.jikos.cz> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="wj9ZLJVQDRFjGSdK" In-Reply-To: <20140122120533.GE6498@twin.jikos.cz> Sender: linux-btrfs-owner@vger.kernel.org List-ID: --wj9ZLJVQDRFjGSdK Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Wed, Jan 22, 2014 at 01:05:33PM +0100, David Sterba wrote: > On Sat, Jan 18, 2014 at 12:50:54PM +0000, Toggenburger Lukas wrote: > > Hello Tomasz > > > > > Have you considered per-file/per-directory selection of raid level? > > > > Sounds great, I haven't thought about it before. > > > > Do you or someone else know what the current state of development is? > > Is someone working on this? > > The feature lacks interface to specify the raid flags per-object. This > is WIP, keyword is 'properties', you'll find some preliminary patches in > the list. This is the ground work for all sorts of fancy tuning. > > The filesystem split into areas with different raid levels will bring > interesting problems regarding free space and operations that cross the > raid levels. But I think it's doable. There's some potentially horrible ENOSPC cases with uneven-sized devices. I need to run some simulations to see how it'll behave... Hugo. -- === Hugo Mills: hugo@... carfax.org.uk | darksatanic.net | lug.org.uk === PGP key: 65E74AC0 from wwwkeys.eu.pgp.net or http://www.carfax.org.uk --- The early bird gets the worm, but the second mouse --- gets the cheese. --wj9ZLJVQDRFjGSdK Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.15 (GNU/Linux) iQIVAwUBUt/JDFheFHXiqx3kAQLoIg//SEHTSa1VrOJUAG6ui392G+Xjt5s58cem zKcL8TNMiCuPoTDtEcBXGp4gQKRTIuRmcVJU2oc2TPETmfERJkkj7UoU7Yur46SM 3L3BEntIgIs+pKIeVTcdcTpFZW51aOdKoUpVuJRq/EtkP3g0T6GhblI8WYHZyRqu 3BYon/A5LyQ2T/zR4tAN3VLaFPfV50/4e+rAQ0ujawQBWhg8ohArahDbffYoHV8l ktnZZggU2FvvjkCPuFWEIjUcUV2vAooOWXsLQKy64ybonTwR3NCX3jt3hVVJ7I4m 3HJ+feczRe/tWmQlGuHmo58WR1XFayyknmcoeLZzyYz0pG5KYnx02FA5vRFlISou yi1PvXDo7w/ar7ha9ypiKnyd9w5KqbHiErkFIuJ53YelIQtieiyKBW8JMFYrintf dSIqOux1su+Q87ZNw57Y6l+NzlhhOvAosq2zDrVX1yNFoZcn1ZYl1vEbBLnjjN/+ DWJSjsGq9YB/Re9cZQbLZTlpHJv6FpMzBjJXBEIUxh/Q+thxUs10ng0A3tvZEKTP +uz/npvuKMSEciYcSnvNfpVbzdPivMTs384CPHyLJKeZcCYMgVShWqQksZaS+2uu nETPouv0MrolNhxHVIShuvwzqZP5jDNzaI+/pTRpAcwRtVytvgzNRDObLHdFNGUF LEdpI2cRSnE= =c5ZT -----END PGP SIGNATURE----- --wj9ZLJVQDRFjGSdK--