Slow transfer with 21140 card

[Mark Fardal]

Hi all,

We've found the problem here, and it's got nothing to do with cards or
cables or tulip drivers or kernels.  It's a network configuration
problem.  The two malfunctioning machines turn out to be sending their
packets off somewhere far away before they make it back to the local
switch.

Thanks to everyone who proposed solutions.  Particular thanks to Mark
Hahn, who suggested I use tcpdump and even interpreted the output for
me.  tcpdump showed that no packets were getting lost or being
re-sent; however, the round-trip time for packets was ~0.04 seconds,
much longer than it should be.  Combining this with a 16-kbyte window
gives a transfer rate of 400 kbytes/second, which is about what I was
getting.  The local guru finally realized what was going on then.
We haven't actually fixed the problem yet but it shouldn't be too hard.

So after all this, we can confirm that the tulip 0.89F driver works
(at least at 10 Mbits/s, probably 100) with a variety of 21140 cards
and a variety of kernels, and that good diagnostics are worth a lot.

thanks,
Mark Fardal
UMass