From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Woodhouse Subject: Re: raidz-like operation? Date: Sat, 11 Jul 2009 15:59:50 +0100 Message-ID: <1247324390.17811.9.camel@macbook.infradead.org> References: <952FC056-F524-420A-9826-F8A287BB2139@karlsbakk.net> Mime-Version: 1.0 Content-Type: text/plain Cc: linux-btrfs To: Roy Sigurd Karlsbakk Return-path: In-Reply-To: <952FC056-F524-420A-9826-F8A287BB2139@karlsbakk.net> List-ID: On Fri, 2009-07-10 at 10:58 +0200, Roy Sigurd Karlsbakk wrote: > I know it's not in yet, but is there a plan to implement raid-z(2)- > like operation? I have heard of plans to integrate with the existing > md-subsystem in the kernel, but I'm not sure if this will be > appropriate comparing this to how things are done in zfs/raid-z. I'm currently working on the basic implementation of RAID5/RAID6 (qv). I don't think there'll be much integration with the md subsystem -- we'll probably just shift the cunning GF arithmetic out into lib/raid6 or something, then let them both use it from there. We do want to do full stripe writes to the RAID[56] parts, so we're going to want to do something like falling back to RAID1 (or to a RAID5 chunk with smaller stripe length) for smaller allocations. That's basically what you're talking about, isn't it? -- David Woodhouse Open Source Technology Centre David.Woodhouse@intel.com Intel Corporation