From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Roger Lucas" Subject: RE: bad performance on RAID 5 Date: Sat, 20 Jan 2007 10:18:28 -0000 Message-ID: <000901c73c7c$5404cb00$8001a8c0@wolverine> References: <45AE9640.1040500@start.no> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Sender: linux-raid-owner@vger.kernel.org To: 'Sevrin Robstad' Cc: linux-raid@vger.kernel.org List-Id: linux-raid.ids Hi Sevrin, Are you sure all the disks are working OK? We saw a problem here with a 4-disk SATA array. The array was working without errors but was _very_ slow. When we checked each disk individually, we found one disk was reporting SMART errors and running slow. We removed it and replaced it with a new disk and the RAID array ran at full speed again. Further tests on the removed disk found that it was having a lot of problems but just about hanging in there (although taking a long time for each operation) - hence the RAID array didn't mark it as faulty. I would check the SMART logs with smartctl to see if anything looks a bit wrong and try benchmarking the disks individually too. - Roger