Power of Two and performance

[dpearcefl]

Using current modern hardware and WD Red drives, does the "power of two" rule/guideline/myth coming into play? I see conflicting information. Some even say if you use compression, this rule does not apply.

Thanks.

 

[dlavigne]

Some even say if you use compression, this rule does not apply.

Not "some", but the guy who wrote (and maintains) ZFS. From http://doc.freenas.org/9.3/freenas_intro.html#zfs-primer:

Some older ZFS documentation recommends that a certain number of disks is needed for each type of RAIDZ in order to achieve optimal performance. On systems using LZ4 compression, which is the default for FreeNAS® 9.2.1 and higher, this is no longer true. See ZFS RAIDZ stripe width, or: How I Learned to Stop Worrying and Love RAIDZ for details.