From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from cantor2.suse.de ([195.135.220.15]:34453 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755153AbaAVMFf (ORCPT ); Wed, 22 Jan 2014 07:05:35 -0500 Date: Wed, 22 Jan 2014 13:05:33 +0100 From: David Sterba To: Toggenburger Lukas Cc: Tomasz Torcz , "linux-btrfs@vger.kernel.org" Subject: Re: Working on Btrfs as topic for master thesis Message-ID: <20140122120533.GE6498@twin.jikos.cz> Reply-To: dsterba@suse.cz References: <8E968DF3B7EC0D40B67B5A9D25675A6A03FC70@MBXSRV03EDU.edu.local> <20140117160436.GA3356@mother.pipebreaker.pl> <8E968DF3B7EC0D40B67B5A9D25675A6A0400BF@MBXSRV03EDU.edu.local> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <8E968DF3B7EC0D40B67B5A9D25675A6A0400BF@MBXSRV03EDU.edu.local> Sender: linux-btrfs-owner@vger.kernel.org List-ID: 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.