From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stan Hoeppner Subject: Re: O_DIRECT to md raid 6 is slow Date: Mon, 20 Aug 2012 00:42:05 -0500 Message-ID: <5031CE2D.8030600@hardwarefreak.com> References: <502D6B0A.6090508@xs4all.net> <502DF357.8090205@hardwarefreak.com> <502E2817.8040306@xs4all.net> <502F237D.6060806@hardwarefreak.com> <502F698C.9010507@msgid.tls.msk.ru> <50305AB9.5080302@hardwarefreak.com> <5030F1C6.90205@hesbynett.no> <50317804.9010701@hardwarefreak.com> <20120820100134.22b2b056@notabene.brown> <5031C0A9.60803@hardwarefreak.com> <20120820051951.GC19235@dastard> Reply-To: stan@hardwarefreak.com Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20120820051951.GC19235@dastard> Sender: linux-raid-owner@vger.kernel.org To: Dave Chinner Cc: NeilBrown , David Brown , Michael Tokarev , Miquel van Smoorenburg , Linux RAID , LKML@dastard.hardwarefreak.com List-Id: linux-raid.ids On 8/20/2012 12:19 AM, Dave Chinner wrote: > Oh, you're probably complaining about that write number. I wasn't complaining. You know me better than that. The cops caught me robbing a bank. Under pressure, I pointed at you and said "He gave me the gun and ammo!". ;) Of course it was completely my responsibility for shooting myself in the foot with it. :) > Either way, the point I was making in the original post stands - > RAID6 sucks balls for most workloads as they only do small writes in > comparison to the stripe width of the volume.... Agreed. Which was the point I originally made in this thread. "We" simply got a minor detail wrong. It seems folks on the linux-raid list like to split every hair 2^6 times, with extremely valid points getting lost when the discussion drops into the weeds. Sorry I dragged you into this Dave. -- Stan