Tuning Linux ZFS

Edit /etc/modprobe.d/zfs.conf

# Set use max memory at half of system memory (ex. 4GB/2)
options zfs zfs_arc_max=2147483648

# Increase scrub/resilver worker
options zfs zfs_vdev_scrub_min_active=24
options zfs zfs_vdev_scrub_max_active=64

# Increase sync write
options zfs zfs_vdev_sync_write_min_active=8
options zfs zfs_vdev_sync_write_max_active=32

# Increase sync reads
options zfs zfs_vdev_sync_read_min_active=8
options zfs zfs_vdev_sync_read_max_active=32

# Increase async reads
options zfs zfs_vdev_async_read_min_active=8
options zfs zfs_vdev_async_read_max_active=32

# Increase async write
options zfs zfs_vdev_async_write_min_active=8
options zfs zfs_vdev_async_write_max_active=32

Save and reboot system to active configuration