Subject: Re: 3c905b Ethernet Cards
To: NetBSD Networking Technical Discussion List <>
From: Matthias Scheler <>
List: tech-net
Date: 02/17/1999 13:30:07
On Wed, Feb 17, 1999 at 04:17:59AM -0500, Greg A. Woods wrote:
> I haven't actually had a chance to do any really good benchmarking with
> anything TCP related, never mind ttcp, but plain old 'ping -f' suggests
> to me that the "fxp" driver is a quite decent driver ...

This test method is bad. If you test the fxp driver with "ttcp" in UDP mode
it gets good results, too. But if you use TCP mode or try to copy files via
NFS/UDP you will not even get full 10MB/Sec ethernet speed.

It looks like the fxp driver causes lots of data corruption errors which
are neither detected by "ping -f" nor by a simple UDP benchmark. But
TCP and NFS/UDP will suffer due to the necessary retransmissions.

> ... particularly if you put some decent hardware behind it,

Is a Pentium II 400 sitting on a BX board with 256MB memory "decent" enough?

I suggest you try running "ttcp -r -s" on one and "ttcp -t -s first-machine"
on the other machine and post the results. I would really like to see
your numbers.


Matthias Scheler