[ofa-general] [RFP] support for iWARP requirement - active connect side MUST send first FPDU

[Glenn Grundstrom]

> > That is what I've been trying to push.  Both MVAPICH2 and 
> OMPI have been 
> > open to adjusting their transports to adhere to this requirement.
> > 
> > I wouldn't mind implementing something to enforce this in 
> the IWCM or 
> > the iWARP drivers IF there was a clean way to do it.  So far there 
> > hasn't been a clean way proposed.
> 
> Why can't either uDAPL or iW CM always do a send from the active to 
> passive side that gets stripped off?  From the active side, the first 
> send is always posted before any user sends, and if necessary, a user 
> send can be queued by software to avoid a QP/CQ overrun.  The 
> completion 
> can simply be eaten by software.  On the passive side, you have a 
> similar process for receiving the data.

This is similar to an option in the NetEffect driver.  A zero byte
RDMA write is sent from the active side and accounted for on the
passive side.  This can be turned on and off by compile and module
options for compatibility.

I second Sean's question - why can't uDAPL or the iw_cm do this?

> 
> (Yes this adds wire protocol, which requires both sides to 
> support it.)
> 
> - Sean
>