Re: [Qemu-devel] [PATCH] block/quorum: add simple read pattern support

[Liu Yuan]

On Fri, Jul 11, 2014 at 08:06:36AM -0600, Eric Blake wrote:
> On 07/10/2014 09:01 PM, Liu Yuan wrote:
> > This patch adds single read pattern to quorum driver and quorum vote is 
> > default
> > pattern.
> > 
> > For now we do a quorum vote on all the reads, it is designed for unreliable
> > underlying storage such as non-redundant NFS to make sure data integrity at 
> > the
> > cost of the read performance.
> > 
> 
> > E.g, Enable single read pattern on 2 children,
> > 
> > -drive driver=quorum,children.0.file.filename=0.qcow2,\
> > children.1.file.filename=1.qcow2,read-pattern=single,vote-threshold=1
> > 
> > [1] http://en.wikipedia.org/wiki/Distributed_Replicated_Block_Device
> > 
> > Cc: Benoit Canet <address@hidden>
> > Cc: Kevin Wolf <address@hidden>
> > Cc: Stefan Hajnoczi <address@hidden>
> > Signed-off-by: Liu Yuan <address@hidden>
> > ---
> >  block/quorum.c | 174 
> > +++++++++++++++++++++++++++++++++++++++++----------------
> >  1 file changed, 125 insertions(+), 49 deletions(-)
> 
> That covers the command line, but what about the *.json changes to allow
> QMP to select this mode when hot-plugging?

Good catch, thanks for reminding.

Yuan