[ofa-general] maximum IB/iWARP max_inline_data size

[Jeff Squyres]

If you ibv_create_qp() with max_inline_data==0:

- Mellanox ConnectX reports a number that is a formula based on  
several values, such as max_send_sge and max_recv_sge.  But its actual  
max inline value (I think Pasha told me) is 1k.

- Chelsio T3 always reports a fixed value back -- its actual  
max_inline_data value (64).

- Preliminary tests with NetEffect NE020 seem to show same behavior as  
T3 (always report back 64).

Our bias in OMPI is to figure such values dynamically at run-time.   
With T3/NE020, it seems to be easy.  Note that if you choose a  
max_inline_data value too large, ibv_create_qp will simply fail.  So  
how can we figure out what the max_inline_data value is for Mellanox  
adapters at run-time?  (I'd prefer not to repeatedly trying to create  
a QP with increasing values of max_inline_data until it fails).

Thanks!

-- 
Jeff Squyres
Cisco Systems