[Cluster-devel] fallocate vs O_(D)SYNC

[Christoph Hellwig]

On Wed, Nov 16, 2011 at 02:39:15PM +0100, Jan Kara wrote:
> > This would work fine with XFS and be equivalent to what it does for
> > O_DSYNC now.  But I'd rather see every filesystem do the right thing
> > and make sure the update actually is on disk when doing O_(D)SYNC
> > operations.
>   OK, I don't really have a strong opinion here. Are you afraid that just
> calling fsync() need not be enough to push all updates fallocate did to
> disk?

No, the point is that you should not have to call fsync when doing
O_SYNC I/O.  That's the whole point of it.