TESTERS: if_sis patch

[Sam Leffler]

> Please try out this patch if you have a "sis" based network card.
> 
> It sets a 400usec interrupt holdoff, and this seems to have a profound
> impact on network performance.
> 
> The patch is relative to FreeBSD-current but probably applies on
> 5.0, 5.1 and even 4.x as well.
> 
> In my tests, using a soekris 4801 computer I have found:
> 
> 	fetch(1)'ing a ftp:// file from a server on the local segment
> 	is 43.2% +/-0.7% faster (from around 385 to 640 kBps).
> 
> 	FTP of the same file is 10.6% +/-1.2% faster (from 3.11 to
> 	3.44 MB/sec)
> 
> 	Checking out src/sbin from a NFS mounted CVSROOT was 17.0%
> 	+/-1.0% faster.

It is especially important that folks with Soekris 45xx boards try this.
My tests appeared to indicate there might be issues, but my operating
environment is so different from -current that is was hard to tell if the
problems I saw (lost packets) were due to this change or others.

	Sam