From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pieter De Wit Subject: Is partition alignment needed for RAID partitions ? Date: Mon, 30 Dec 2013 10:04:35 +1300 Message-ID: <52C08E63.8020800@insync.za.net> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Sender: linux-raid-owner@vger.kernel.org To: linux-raid List-Id: linux-raid.ids Hi List, I am taking advantage of the holiday season by testing some NAS devices for work. This now allows me to rebuild my home storage. My current setup is as follow: /dev/sda 250 gig drive (/boot is mounted here since I had no other use for the drive) /dev/sdb 2TB drive /dev/sdc 2TB drive /dev/sdb and sdc has two MD devices on them, a RAID1 and a RAID0 device. /dev/sdb and sdc was taken out of a MAC server, so the partition table is a mess, I want to rebuild them. All of these house LVM PV's The RAID1 device contains all my "critical" data ( root device, logs, photos etc) while the RAID0 device contains all data I have other sources for. So my question is, do I need to align the partitions for the raid devices ? These are desktop grade drives, but for the RAID0 device I saw quite low throughput (15meg/sec moving data to the NAS via gig connection). I just created a RAID1 device between /dev/sda and an iSCSI target on the NAS, and it synced at 48meg/sec, moving data at 30meg/sec - double that of the RAID0 device. I would have expected the RAID0 device to easily get up to the 60meg/sec mark ? Cheers, Pieter