Re: NetBSD 5.0.1 Networking Message

[Manuel Bouyer <bouyer%antioche.eu.org@localhost>]

On Sat, Aug 15, 2009 at 06:39:41PM -0400, Erik Winkler wrote:
> I am running NetBSD 5.0.1 (Generic PPC Kernel) on PowerMac 7600 with a  
> powerpc 7455 processor upgrade card running at 1 Ghz.  I have 2 of the  
> following ethernet cards installed (per NetBSD dmesg output):
> 
> 3Com 3c905B-TX 10/100 Ethernet (rev. 0x30)
> 
> For some reason I keep getting the following messages and I don't see  
> the cause:
> 
> ex1:  transmit underrun (9000) @20

This means the 3com chip couldn't get data fast enough from the PCI bus.
THis is usually because another device (or possibly the CPU) holds the PCI
bus for too long. It's probably happening only once in a while (no more than
once every 256 packets) otherwise it would have bumped the TX threshold.

-- 
Manuel Bouyer <bouyer%antioche.eu.org@localhost>
     NetBSD: 26 ans d'experience feront toujours la difference
--