From mboxrd@z Thu Jan 1 00:00:00 1970 From: keld@keldix.com Subject: Re: raid10n2/xfs setup guidance on write-cache/barrier Date: Thu, 15 Mar 2012 18:15:49 +0100 Message-ID: <20120315171548.GA30531@www5.open-std.org> References: <4F61803A.60009@hardwarefreak.com> <20321.63389.586851.689070@tree.ty.sabi.co.UK> <20120315152548.GA25194@www5.open-std.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: Sender: linux-raid-owner@vger.kernel.org To: Jessie Evangelista Cc: Linux RAID , Linux fs XFS List-Id: linux-raid.ids On Fri, Mar 16, 2012 at 12:52:19AM +0800, Jessie Evangelista wrote: > Hi keld, > > On Thu, Mar 15, 2012 at 11:25 PM, wrote: > > On Thu, Mar 15, 2012 at 02:07:25PM +0000, Peter Grandi wrote: > >> >>> I want to create a raid10,n2 using 3 1TB SATA drives. > >> >>> I want to create an xfs filesystem on top of it. The > >> >>> filesystem will be used as NFS/Samba storage. > >> > >> Consider also an 'o2' layout (it is probably the same thing for a > >> 3 drive RAID10) or even a RAID5, as 3 drives and this usage seems > >> one of the few cases where RAID5 may be plausible. > > > > Well, for a file server like NFS/Samba, you could also consider raid10,f2. > > I would think you could get about double the read performance compared to n2 and o2 > > layouts, and also for individual read transfers on a running system > > you would get somthing like double the read performance. > > Write performance could be somewhat slower (0 to 10 %) bot as users > > are not waiting for writes to complete, they will probably not notice. > > I also plan to try raid10f2. Did you do your own benchmarks or are you > quoting someone elses? Both, look at our wiki: https://raid.wiki.kernel.org/articles/p/e/r/Performance.html Best regards keld