How to disable hard disk write cache?

[Matthias Andree]

Am 16.09.2014 um 16:09 schrieb Xin Li:

> Modern SATA/SAS/SCSI devices usually comes with the capability of
> tagged commands, allowing the OS to know when a write buffer is on
> stable storage.  With this, file systems can easily implement the
> right semantics and recover from e.g. a power outage, etc.

Yes, they *can easily implement* that, but which file systems in FreeBSD
*actually do* that?

Do we have a list which file systems are safe to use with WCE=1 as long
as they do NCQ?

And what do you need to do on those Samsung drives where NCQ is flakey
(HD103SI for one)?