Finally, we start installing the ZFS packages and start the RAIDZ2 set-up (no screenshot):

apt-get zfsutils-linux

For several reasons, I chose to use:

• vdevs created “by-id”:
  • as per advice from multiple places online, using the “easier” /dev/sdx identifier may break things should the order be changed (e.g. you swapped cable ends or drive cages, etc.)
• lz4 compression
  • as per statistics from some places, the “cost” of LZ4 is relatively low/negligible

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Attempting to implement ZFS and the decisions that go into it is enough to make any newbie give up (and/or get terribly confused)…

Unfortunately, Google does not help, what with old information (e.g. installation instructions: old vs. new; possibly outdated information) and different “package variations” of ZFS (e.g. Ubuntu-native ZFS packages vs. ZFS-native), and the endless arguments on the “correct number of disks” for RAIDZ/2 (mirrored vdevs only? RAIDZ? RAIDZ2? mirrored RAIDZ/2? block size?)…

I read through all those articles linked above, including some other helpful(?) ones:

• https://wiki.ubuntu.com/ZFS (proven to be mostly incorrect/misleading info!)
• http://sphinx.freenas.org/zfsprimer.html#zfs-primer
• https://icesquare.com/wordpress/how-to-improve-zfs-performance/
• https://icesquare.com/wordpress/zfs-performance-mirror-vs-raidz-vs-raidz2-vs-raidz3-vs-striped/ (probably not realistic due to prandom files)
• https://github.com/zfsonlinux/zfs/wiki/faq

Some other “associated” links/articles/comments/posts that I came across:

• https://forums.freebsd.org/threads/21005/#post-124327 (might be useful to force 4K alignment?)
• https://icesquare.com/wordpress/how-to-improve-rsync-performance/

My decision?

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