ZFS

Since fall 2015 the default compression algorithm in ZOL is LZ4 and since choosing compression=on means activate compression using default algorithm then your pools are using LZ4 → http://open-zfs.org/wiki/Performance_tuning#Compression

# Check if LZ4 is active
zpool get feature@lz4_compress rpool

• ZPool is the logical unit of the underlying disks, what zfs use.
• ZVol is an emulated Block Device provided by ZFS
• ZIL is ZFS Intent Log, it is a small block device ZFS uses to write faster
• ARC is Adaptive Replacement Cache and located in Ram, its the Level 1 cache.
• L2ARC is Layer2 Adaptive Replacement Cache and should be on an fast device (like SSD).

• ZFS: Tips and Tricks
• Install on a high performance system

For nodes without local-zfs, i.e. Debian based custom system it is possible to add local-zfs storage later.

zpool create -f -o ashift=12 rpool /dev/sdb
zfs set compression=lz4 rpool
zfs create rpool/data
 
# You can get a list of available ZFS filesystems with:
pvesm zfsscan
 
zpool status -v
zfs list