LVM with cache
Create a logical volume with nvme cache.
vgcreate storage /dev/sdb /dev/nvme0n1
lvcreate -L 6T -n lv storage /dev/sdb
lvcreate -L 900G -n lv_cache storage /dev/nvme0n1
lvcreate -L 9G -n lv_meta storage /dev/nvme0n1
lvconvert --type cache-pool --cachemode writethrough --poolmetadata storage/lv_cache_meta storage/lv_cache
lvconvert --type cache --cachepool storage/lv_cache storage/lv