Databases If databases data is stored on a ZFS filesystem, it’s better to create a separate dataset with several tweaks: zfs create -o recordsize=8K -o primarycache=metadata -o logbias=throughput -o mountpoint=/path/to/db_data rpool/db_data recordsize: match the typical RDBMSs page size (8 KiB) primarycache: disable ZFS data caching, as RDBMSs have their own logbias: essentially, disabled log-based writes, relying on the RDBMSs’ integrity measures (see detailed Oracle post)

ZFS native encryption: zpool create -o ashift=12 \ -O acltype=posixacl -O canmount=off -O compression=lz4 \ -O dnodesize=auto -O normalization=formD -O relatime=on -O xattr=sa \ -O encryption=aes-256-gcm -O keylocation=prompt -O keyformat=passphrase \ -O mountpoint=/ -R /mnt rpool ${DISK}-part4

Then create a file with the key (ex 31 x 1) echo 1111111111111111111111111111111 > /key.txt Then create an encrypted filesystem ex enc on your "pool" based on that key zfs create -o encryption=0n keyformat=raw -o keylocation=file:///key.txt pool/enc

zfsembedsdatadirectlyinalogentry.Forlargeval-ues,itwritesdatatodiskredirect-on-write,andstoresapointerinthelog[21].Thisgiveszfsfastdurabilityforsmallwritesbyflushingthelog,avoidstheoverheadofwritinglargevaluestwice,andretainstherecoveryse-manticsofdatajournaling.Ontheotherhand,btrfs[26]usesindirectionforallwrites,regardlessofsize.Itwritesdatatonewly-allocatedblocks,andrecordsthosewriteswithpointersinitsjournal