Performance problems with a Via Rhine II and a rtl8139C NIC on a Via Epia MB

[Guido Winkelmann]

Hi

I have here a Via Epia V8000 Mainboard with an onboard Via VT6102 Rhine II 
Ethernetcontroller and a Realtek 8139C NIC plugged into the only PCI slot.
The machines main purpose is to serve as a NAT router for an ADSL connection 
for a small home network. (But I was also planning on deploying it as a 
fileserver, nameserver, mailserver and whatnot in the near future.)

The problem is that receiving data from the local network is really slow.

Receiving data from the local network using the Via Rhine adapter gives a data 
rate of 588.2 Kilobytes/s, using the Realtek adapter it's only 37.9 
Kilobytes/s.

Sending data to a host on the local net results in a data rate of 9.3 
Megabytes/s when using the Via Rhine adapter and 5.2 Megabytes/s when using 
the Realtek adapter.

When receiving data over the Via Rhine adapter, I see this message popping up 
about once per second on the system console: "vr0: rx packet lost".

When I take the Realtek card out of the computer, the desccribed problem with 
the Via adapter disappears completely. When I disable the Via Rhine adapter 
in the BIOS setup, the problem with the Realtek card persists. The described 
problems will also persist if I exchange the Realtek 8139 for an older 
Realtek 8029 10MBit card.

(btw, If you ever happen to wonder why your Computer with a Via Epia board 
won't start anymore after you removed or plugged in a PCI card, try 
unplugging the power cable for a second.)

This is what FreeBSD says when detecting the Via Rhine card:
vr0: <VIA VT6102 Rhine II 10/100BaseTX> port 0xe800-0xe8ff mem 
0xe3000000-0xe30000ff irq 11 at device 18.0 on pci0

And this is what it says when detecting the Realtek card:
rl0: <RealTek 8139 10/100BaseTX> port 0xec00-0xecff mem 0xe3001000-0xe30010ff 
irq 15 at device 20.0 on pci0

FreeBSD is a RELENG_5_2 checked out shortly after the release of 5.2, but a 
short experiment with the latest Knoppix CD suggested that the problem might 
be independent of the OS.

I have also tried booting up FreeBSD with verbous logging once, the resulting 
dmesg output can be found here:
http://www.stud.uni-hannover.de/~guido83/dmesgoutputverbous
(This also might be of interest for those of you wondering about the specifics 
of more recent Via boards)

I'd be glad if you could help me with that.

	Guido Winkelmann