[openib-general] DAPL for openib

[Sean Hefty]

On Tue, 31 Aug 2004 17:36:34 -0400
Hal Rosenstock <halr at voltaire.com> wrote:

> For most classes this is true. For CM, there might be a couple of
> versions supported.

Still, the table is small, consuming only a few bytes.
 
> > The class table is about 8 entries long, 
> 
> This of course depends on what services are running on the node.

Correct.  There are only a handful of defined classes.  The table could be larger if there were several vendor defined classes.  Worst case is a table with 256 entries, with the table duplicated for each version.

> > The method array is only needed if a client doesn't register to 
> > receive all unsolicited MADs for a specific class.
> 
> This means that for any class, the IB MAD layer needs to know
> which methods are used for unsolicited MADs. 

I don't think that the MAD layer needs to know this information.  It needs to know if a received MAD was sent in response to a previously sent one.  In general, this means checking the response bit.  If not, it will route the MAD to whichever client is registered to receive unsolicited MADs that match the MADs version / class / method / attribute / etc.  If the MAD is a response, it can route based on the transaction ID.

Of course there are exceptions to the rule of simply checking the response bit, like RMPP.