Subject: Re: Receiver ring buffer overrun ?
To: Uwe Klaus <uklaus@info015.informatik.uni-leipzig.de>
From: Jason Thorpe <thorpej@nas.nasa.gov>
List: current-users
Date: 06/28/1995 07:28:23
On Wed, 28 Jun 1995 11:00:50 +1480152 (MET DST) 
 Uwe Klaus <uklaus@info015.informatik.uni-leipzig.de> wrote:

 > 	/netbsd: ed0: warning - receiver ring buffer overrun
 > Should I worry about it? 
 > Can I modify the sources to increase the buffer size? And how.

(You neglected to mention whether or not this was on an i386 or amiga; 
I'll just assume i386...)

This message is referring to the ring buffer on the card itself.

Whenver this happens, it's safe to assume that you've dropped 
whatever packets that haven't yet been pulled off the card.

This ususally happens when:

	a)  _LOTS_ of traffic directed at your machine and/or broadcast
	    storms.

	b)  Fairly slow CPU -- driver can't get to the packets fast enough.

	c)  Something else happens at a higher priority for too long
	    and `incoming packet' interrupts are either missed or not handled
	    in time.  (Like, for example, you drop into the DDB while
	    your machine is running mrouted and someone on your
	    subnet is watching the space shuttle mision :-)

...plus any number of other conditions.  The 16-bit SMC in my 486/66 
usually only encounters condition `c' above.

Anyhow, maybe this gives you some ideas when looking to solve the problem...

Ciao.

--------------------------------------------------------------------------
Jason R. Thorpe                                       thorpej@nas.nasa.gov
NASA Ames Research Center                               Home: 408.866.1912
NAS: M/S 258-6                                          Work: 415.604.0935
Moffett Field, CA 94035                                Pager: 415.428.6939