Only diff is max_sectors_kb, 512->4096 That matches the iostat, 8k there is in 512b sectors which matched 4k max sectors. I don't see where the patch is that breaks that in linux-stable, but it is worth a try to boot a bad kernel and set 512 in /sys.
Later to tune for your raid case with so many disks you might consider setting also /sys/class/block/sdb/queue/rotational = 0 Locality doesn't mean a lot to your setup and might safe some cpu cycles. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1668557 Title: Write performance regression severely affecting hpsa controllers To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1668557/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
