[openib-general] How about ib_send_page() ?

[Sean Hefty]

Fab Tillier wrote:
> Ok, so this question is from a noob, but here goes anyway.  Why can't IPoIB
> advertise a larger MTU than the UD MTU, and then just fragment large IP
> packets up if they need to go over the IB UD transport?  Is there any reason
> this couldn't work?  If it does, it allows IPoIB to expose a single MTU to
> the OS, and take care of the rest under the covers.
> 
> Just a thought.

I don't remember seeing a response to this.  Something like this could work. 
  I guess one disadvantage is that it can be less efficient if you lose a 
lot of packets.  TCP would resend an entire MTU (as seen by TCP) of data if 
only a single IB packet were lost.

- Sean