From mboxrd@z Thu Jan 1 00:00:00 1970 From: Wols Lists Subject: Re: Fwd: Installing Linux directly onto RAID6 Array........... Date: Sun, 24 May 2015 13:41:13 +0100 Message-ID: <5561C6E9.3060706@youngman.org.uk> References: <555294A0.6040703@websitemanagers.com.au> <5561B237.4040709@youngman.org.uk> <5561BCA4.4060904@fnarfbargle.com> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <5561BCA4.4060904@fnarfbargle.com> Sender: linux-raid-owner@vger.kernel.org To: Brad Campbell , Mikael Abrahamsson , Another Sillyname Cc: linux-raid@vger.kernel.org List-Id: linux-raid.ids On 24/05/15 12:57, Brad Campbell wrote: > On 24/05/15 19:12, Wols Lists wrote: > >> Don't bother raid'ing swap at all! If you set the priority equal on all >> the swaps, linux will do a raid 0 for you and, frankly, what's the point >> of doing raid on your swap partition? You really shouldn't (in normal >> usage) be using swap at all. > > When you develop a bad block in one of your non-RAID swap partitions and > you spend a week trying to figure out why processes randomly die for no > apparent reason you'll reconsider that attitude. > aiui raid won't help you at all here, will it? Firstly, if you get write failures, the hard drive should swap the block, or the write layer should swap it. Nothing to do with raid whatsoever. And if you get read errors, well, aiui, raid won't help here either - especially with mirrored raid, you just get a read failure. Raid does NOT give you error recovery unless the drive physically fails, and if it's a bad block it gets fixed at the disk or disk driver level - well below the raid driver. Cheers, Wol