zfs tune article

https://docs.oracle.com/cd/E53394_01/html/E54801/zfspools-4.html

http://open-zfs.org/wiki/Performance_tuning

https://pthree.org/2012/12/13/zfs-administration-part-viii-zpool-best-practices-and-caveats/

http://jrs-s.net/2015/02/06/zfs-you-should-use-mirror-vdevs-not-raidz/