new version of polling for FreeBSD 6.x

[Fabien THOMAS]

> Haven't tested RELENG_4 performance in a controlled environment and
> thus can't answer the question directly.  However using fastforward
> on 6 and 7 is key to good performance.  Without it you're stuck at
> some 150-200kpps, perhaps 300kpps.  With it you get to 500-800kpps.
>
>

To show that pps is mainly related to CPU freq (with high end  
component):

FreeBSD 6.2, packet size is 64bytes and value L3 Mb/s between the two  
only CPU change.

Xeon Woodcrest		2.33	3.00	1,287
pollng 1CPU:		210		257		1,224		
pollng 2CPU:		329		396		1,204
pollng 1CPU fastfwd:	291		364		1,251
pollng 2CPU fastfwd:	455		536		1,178

warn: this is not the same hardware than in the pdf.