improved TSO interface needed

[Andre Oppermann]

Kip Macy wrote:
>> 64K is the max, and I believe that is taking into account the headers.
>> What size are you seeing that is larger?  Even if an mbuf chain comes
>> down that large, it does NOT form a single packet, it is packetized by
>> the hardware into MTU size, as I said, on the wire, ie as the receiver
>> sees it, its just a lot of packets. The only question is whether the
>> transmit hardware can handle it. Do you have eivdence of some
>> hardware that supports TSO in the driver that cant??
> 
> I see this when torture testing a couple of different 10GigE cards
> running at line rate.

Your reported overshooting of 10 bytes is due to a buglet that didn't
appear until now.  Please try this fix:

  http://people.freebsd.org/~andre/tso_fix-20070226.diff

-- 
Andre