Does UFS2 send BIO_FLUSH to GEOM when update metadata (with softupdates)?

[Ivan Voras]

On 23.11.2011. 20:44, Kostik Belousov wrote:

> The only requirement of the SU is that writes reported as done by disk
> driver are indeed safely landed in the involatile storage.

Well, yes, that was the idea, and it works surprisingly well even though 
hardware today lies about it.

Some time ago I've written a patch as an learning excercise which issues 
a BIO_FLUSH when it thinks SU needs it - it may or may not be correct so 
I didn't even try to commit it:

http://people.freebsd.org/~ivoras/diffs/fsync_flush.patch

Of course, reviews are welcome :)