ARRAYS="" DISKS="" for field in `cat /proc/mdstat | grep "active raid6"` do if [[ "x${field:0:2}x" == "xmdx" ]] then ARRAYS="$ARRAYS $field" elif [[ "x${field:0:2}x" == "xsdx" ]] then DISKS="$DISKS ${field:0:3}" fi done for disk in $DISKS do # read-ahead to 16MB blockdev --setra 16384 /dev/$disk # Queue Tuning echo 1024 > /sys/block/$disk/queue/read_ahead_kb echo 256 > /sys/block/$disk/queue/nr_requests # disable NCQ echo 1 > /sys/block/$disk/device/queue_depth done for array in $ARRAYS do # read-ahead to 64MB blockdev --setra 64536 /dev/$array # stripe-cache size echo 16384 > /sys/block/$array/md/stripe_cache_size done-- LeoGalambos - 28 Oct 2018