[c-nsp] low end gige with jumbo frames

[A.L.M.Buxey at lboro.ac.uk]

Hi,

> It is at least configurable:
> 
> 2970#sh sys mtu
> 
> System MTU size is 1546 bytes
> System Jumbo MTU size is 9000 bytes
> 
> Don't know if it's working, though

2970g-24tse can do jumbo frames - and its a system wide setting. setting
the ports to 9000 MTU does deleiver the expected improvement
(benchmarked with 2 fast systems doing a RAM<->RAM transfer
with Intel Gig network cards)

alan