Eu fiz isso no debian 8. sda - 3tb sata. sdb - 256 ssd. Funciona incrível ...
aptitude install thin-provisioning-tools
pvcreate /dev/sdb1
vgextend vg0 /dev/sdb1
lvcreate -n CacheDataLV -l 99%FREE vg0 /dev/sdb1
lvconvert --type cache-pool vg0/CacheDataLV --cachemode writeback
lvconvert --type cache --cachepool vg0/CacheDataLV vg0/root
vi / etc / initramfs-tools / hooks / dmbootscript
#!/bin/sh
PREREQ="lvm2"
prereqs()
{
echo "$PREREQ"
}
case $1 in
prereqs)
prereqs
exit 0
;;
esac
if [ ! -x /usr/sbin/cache_check ]; then
exit 0
fi
. /usr/share/initramfs-tools/hook-functions
copy_exec /usr/sbin/cache_check
manual_add_modules dm_cache dm_cache_mq
e finalmente: chmod + x / etc / initramfs-tools / hooks / dmbootscript update-initramfs -u -v -k all
dmsetup status vg0-root
dmsetup ls --tree
Com certeza eu corro update-initramfs -u -v -k todos Toda a atualização do kernel.