> ОхЪ.
> XFS, к примеру, без них бесполезна.ЁхЪ.
http://xfs.org/index.php/XFS_FAQ#Write_barrier_support.
Many hardware RAID have a persistent write cache which preserves it across power failure,
interface resets, system crashes, etc. Using write barriers in this instance is not
recommended and will in fact lower performance. Therefore, it is recommended to turn off
the barrier support and mount the filesystem with "nobarrier", assuming your RAID controller
is infallible and not resetting randomly like some common ones do. But take care about the
hard disk write cache, which should be off.