[rrego]

So from reading the XFS FAQ linked in the article(http://xfs.org/index.php/XFS_FAQ#Write_barrier_support.), does this mean that Moto Z never flushes the cache to disk?

Wouldn't the cache HAVE to be flushed as it fills up at some point to maintain coherence.

[idrae]

Yes, it has to be flushed from time to time. Normally this happens automatically when it is needed. fsync() just forces a direct flush.