How to expand the udp_sendspace

[Chris Johns]

Busalski, Wilfried wrote:
> 
> I need to send more than the 9216 Bytes in a udp packet.

The data passed into a send call will be broken up (fragmentation) into MTU 
size packets for the physical transporting. If you send more than the MTU you 
will not have a 1:1 relationship with the packets on the physical interface.

> How do I expand the size of the udp_sendspace without changing the 
> source of  udp_usrreq.c ?

Did you try the setsockopt [1] and SO_SNDBUF ?

> 
> Any Ideas ?
> 

Take a look at the ttcp code in:

  http://www.rtems.org/ftp/pub/rtems/4.9.2/network-demos-4.9.2.tar.bz2

I think it sends large UDP packets to get the highest line rate possible.

Regards
Chris

[1] FreeBSD Man page for getsockopt
  http://www.freebsd.org/cgi/man.cgi?query=getsockopt&format=html