On Sun, 7 Dec 1997 18:00:19 -0500,
Mark and Ailien <fee@tetranet.net> wrote:
> 
>   This question relates to an SE/30 I have running NetBSD 1.3Beta (the
> distribution as of mid-November).  I have an Ethernet card (A daynaport I
> believe) that NetBSD is recognizing fine.  My problem is, when using it for
> various things (ftp, xdmcp, nfs) I get something along the lines of:
> 
> ae0: receive buffer ring overflow

I used to see a lot of this on my SE/30 with Kinetics EtherPORT SE/30
Ethernet card.  Are you sure yours is a DaynaPort?  I'm asking it
because Danya bought the rights to EtherPORT and now they're
distributing the MacOS device driver for EtherPORT.  Besides,
DaynaPort E/30, AFAIK, uses SONIC, not NIC, so it should be recognized
(if at all) as sn0 rather than ae0.

The reason of this error is simple: (machine speed)x(buffer size) is
too small for the amount of incoming data that has to be processed.

> I realize that this is not precise, but it is very close, and of course it
> makes sense what is happening.  Is there a source file that I can modify to
> increase the receive buffer size?  I am running a system with 8MB of RAM,
> so memory is a tight issue.  Could that possibly be the cause?

No, like Bill said, you can't increase (or decrease, for that matter)
buffer size because it's a chip or two on the card.  EtherPORT has
only 8KB of it, and even worse, it's 8-bit width as opposed to most
others' 16-bit.

Anyway, "receive buffer ring overrun" (I think it's overrun, not
overflow, but I could be wrong) does no harm.  Your SE/30's just
telling you that it's not fast enough ;-)

Ken