Heads up

[Warner Losh]

The CAM I/O scheduler has been committed to current. This work is described
in https://people.freebsd.org/~imp/bsdcan2015/iosched-v3.pdf though the
default scheduler doesn't change the default (old) behavior.

One possible issue, however, is that it also enables NCQ Trims on ada SSDs.
There are a few rogue drives that claim support for this feature, but
actually implement data corrupt instead of queued trims. The list of known
rogues is believed to be complete, but some caution is in order.

Warner