On Tue, May 04, 2010 at 08:56:14PM +0200, Christoph Hellwig wrote:
> On Tue, Apr 20, 2010 at 02:46:35AM +0100, Jamie Lokier wrote:
> > Does this mean that virtio-blk supports all three combinations?
> >
> >1. FLUSH that isn't a barrier
> >2. FLUSH that is also a barrier
> >3. Barrier t
On Tue, Apr 20, 2010 at 02:46:35AM +0100, Jamie Lokier wrote:
> Does this mean that virtio-blk supports all three combinations?
>
>1. FLUSH that isn't a barrier
>2. FLUSH that is also a barrier
>3. Barrier that is not a flush
>
> 1 is good for fsync-like operations;
> 2 is good for jo
On Tue, Apr 20, 2010 at 02:22:58PM +0100, Paul Brook wrote:
> > Does this mean that virtio-blk supports all three combinations?
> >
> >1. FLUSH that isn't a barrier
> >2. FLUSH that is also a barrier
> >3. Barrier that is not a flush
> >
> > 1 is good for fsync-like operations;
> > 2
> Does this mean that virtio-blk supports all three combinations?
>
>1. FLUSH that isn't a barrier
>2. FLUSH that is also a barrier
>3. Barrier that is not a flush
>
> 1 is good for fsync-like operations;
> 2 is good for journalling-like ordered operations.
> 3 sounds like it doesn't
Michael S. Tsirkin wrote:
> I took a stub at documenting CMD and FLUSH request types in virtio
> block. Christoph, could you look over this please?
>
> I note that the interface seems full of warts to me,
> this might be a first step to cleaning them.
>
> One issue I struggled with especially is
