RELENG_8 ignoring TCP window size? [Was: Re: Help for TCP understanding wanted, ACK-MSS-Window [Was: Re: best practice to watch TCP parms of established sockets]]

[Jeremy Chadwick]

On Thu, Feb 25, 2010 at 10:03:01AM +0100, Harald Schmalzbauer wrote:
> Since I could only capture "bad IP length" packets with checsum
> offloading enabled on the em, I guess it does also IP checksum
> offloading, not only TCP. I'll have to set up a port mirroring test
> bed to get the line packets. I hope I'll find the rfc1323 slowdown
> and the difference between FreeBSD clients and Windows clients. But
> at the moment I don't have spare equipment.

Worth pointing out: the version of Windows you're testing with matters
greatly.  RFC1323 isn't enabled by default in some versions of Windows,
and in other versions the default/min/max window sizes on Windows are
set absurdly small.

-- 
| Jeremy Chadwick                                   jdc at parodius.com |
| Parodius Networking                       http://www.parodius.com/ |
| UNIX Systems Administrator                  Mountain View, CA, USA |
| Making life hard for others since 1977.              PGP: 4BD6C0CB |