From mboxrd@z Thu Jan 1 00:00:00 1970 From: Keld Simonsen Subject: Re: migrating from RAID5 to RAID10 Date: Fri, 18 Jun 2010 10:40:28 +0200 Message-ID: <20100618084028.GA23230@rap.rap.dk> References: <20100609151132.GA10082@libra.CS.Berkeley.EDU> <20100611005231.401529c0@natsu> <20100610195851.GA8408@libra.CS.Berkeley.EDU> <4C18F39E.8010600@tmr.com> <20100617072631.09641f48@notabene.brown> <20100617174445.GB8450@libra.CS.Berkeley.EDU> <20100618083053.7df5248b@notabene.brown> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Return-path: Content-Disposition: inline In-Reply-To: <20100618083053.7df5248b@notabene.brown> Sender: linux-raid-owner@vger.kernel.org To: Neil Brown Cc: Gilad Arnold , Bill Davidsen , Roman Mamedov , linux-raid@vger.kernel.org List-Id: linux-raid.ids On Fri, Jun 18, 2010 at 08:30:53AM +1000, Neil Brown wrote: > > 2-drive RAID10 f2 would be expected to provide better read throughput > (possibly twice as fast) at some cost to write throughput. For many people > this is a worthwhile trade-off. So it might be better for you. > Read throughput would degraded down to write throughput (i.e. slower than > RAID1) if the RAID10 were degraded. The slowdown of write thruput is on the raw raid, and on file systems without elevator algorithms. If you employ a file system with an elevator algorithm, then there will be no noticeable slowdown for writes, as witnessed by many benchmarks. best regards keld