mdadm --stop /dev/md0
mdadm -q --create /dev/md0 --chunk=256 --level=raid5 --raid-devices=11 --force --assume-clean /dev/sdb /dev/sdg /dev/sdi /dev/sdh /dev/sdl /dev/sdf /dev/sdm /dev/sdk /dev/sdd /dev/sde /dev/sdc
mkfs -t xfs /dev/md0
mount -t xfs -o nobarrier,inode64 /dev/md0 /fs/md0
echo 1 > /sys/kernel/debug/tracing/events/writeback/balance_dirty_pages/enable
echo 1 > /sys/kernel/debug/tracing/events/writeback/bdi_dirty_ratelimit/enable
echo 1 > /sys/kernel/debug/tracing/events/writeback/global_dirty_state/enable
echo 1 > /sys/kernel/debug/tracing/events/writeback/writeback_single_inode/enable
dd  if=/dev/zero of=/fs/md0/zero-1 status=noxfer &
sleep 300
killall -9 dd