smaller blocksizes with solaris

[jesse butler <Jesse.Butler --at-- Sun.COM>]

Hi,

As communicated earlier, I'm having some trouble using small blocksizes 
with Iperf.  As shown below, I attempt to use 16 bytes, but after the 
warn, it is set to 32 KB.

[jesseb --at-- aion]: ~/iperf/iperf-1.1.1 $ iperf -c aion -w 16
WARNING: TCP window size set to 16 bytes. A small window size
will give poor performance. See the Iperf documentation.
------------------------------------------------------------
Client connecting to aion, TCP port 5001
TCP window size: 32.0 KByte (WARNING: requested 16.0 Byte)
------------------------------------------------------------
[  4] local 129.148.184.208 port 36483 connected


I would like to change the code and rebuild so it will work for me, but 
am a bit stuck.  I've discovered that at some point, a small blocksize 
is getting overridden with a larger size, but I can't find where in the 
code.  I have traced it into lib/tcp_window_size.c and 
setsock_tcp_windowsize(), which in turn calls setsockopt()... but I 
don't see anywhere where if the window size passed in is overridden if 
it's smaller than a certain size.

Anyone have any ideas, see anything, want to bop me on the head for 
missing something obvious?

Thanks,
Jesse