From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stan Hoeppner Subject: Re: "Missing" RAID devices Date: Wed, 22 May 2013 17:43:33 -0500 Message-ID: <519D4A15.7020107@hardwarefreak.com> References: <519B9351.4050708@turmel.org> <519C0B13.3040906@turmel.org> 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: <519C0B13.3040906@turmel.org> Sender: linux-raid-owner@vger.kernel.org To: Phil Turmel , Linux RAID List-Id: linux-raid.ids Sorry for the dup Phil, hit the wrong reply button. On 5/21/2013 7:02 PM, Phil Turmel wrote: ... > ...First is /dev/md1, a small (~500m) n-way > ...as /boot. The other, /dev/md2, uses > ...raid10,far3 or raid6. > > I put LVM on top of /dev/md2, with LVs for swap, ... /tmp Swap and tmp atop an LV atop RAID6? The former will always RMW on page writes, the latter quite often will cause RMW. As you stated your performance requirements are modest. However, for the archives, putting swap on a parity array, let alone a double parity array, is not good practice. -- Stan