On Wed, Dec 12, 2012 at 4:36 PM, Laurent Wandrebeck l.wandrebeck@gmail.com wrote:
Hi there,
I've discovered that most of the hard drives used in our cluster got misaligned partitions, thus crippling perfs. Is there any way to fix that without having to delete/recreate properly aligned partitions, then format it and refill disks ? I'd be glad not to have to toy with moving several 10s of TB disk by disk :D (most disks are JBOD as we're using a fault tolerant network FS, moosefs not to name it). <insert your favorite search engine> wasn't helpful, unfortunately. Drives are ext4, driven by C6 x86_64.
boot the server with a gparted livecd / pxe ; move the partitions around with an offset of 1MB at the start of the disk/volume. I do not know if this trick will work with lvm, in this case you need to move the data around and recreate the volumes with the correct offset.
Have fun!