Re: [Nbd] NBD using SDP

[John Leidel <john.leidel@...17...>]

The patches essentially allow one to take advantage of the transport
layer RDMA capabilities of the fabric medium using the OpenFabrics
software stack.  The most common transport fabric is Infiniband,
although Chelsio 10GbE cards also support the protocol.

You'll probably see the most benefit when using fairly large block sizes
as the transfer mechanisms in OpenFabrics tend to favor large messages
[although, they are building in better support for smaller messages].
I'm not sure what to expect if you mount swap in this manner.  It would
either give you quite a performance boost, or completely hose up the
swap.      

A more complete discussion on SDP is here: 
http://en.wikipedia.org/wiki/Sockets_Direct_Protocol

and here


On Tue, 2007-10-16 at 12:50 +0200, Wouter Verhelst wrote:
> On Mon, Oct 15, 2007 at 06:21:50PM -0500, John Leidel wrote:
> > All... apologies for the random post...
> 
> It's not random ;-)
> 
> > sometime ago I created a simple patch set for NBD to directly utilize
> > the RDMA capabilities of Infiniband via the Sockets Direct Protocol.
> 
> What are the benefits of doing so? I guess I could be pursuaded to
> accept this into nbd-tools mainline, but I'd really have to know what
> these protocols do, and how they benefit NBD.
> 
> Thanks,
>