Re: Proposal: B_ARRIER (addresses wapbl performance?)

[Andrew Doran <ad%netbsd.org@localhost>]

On Tue, Dec 09, 2008 at 08:10:32PM +0100, Joerg Sonnenberger wrote:

> On Tue, Dec 09, 2008 at 10:14:25AM -0800, Jason Thorpe wrote:
> > Repeat: Ordered tags have nothing to do with whether or not a write is  
> > committed to stable storage.  But that is precisely what you want for a 
> > write to a journal.  FUA is the mechanism that is specifically intended 
> > to get the behavior you want for a journal.
> 
> For the journal we only want "written to stable storage before written
> the meta data blocks back".

If no files are open synchronously and nobody has called fsync(), yes.

Andrew