Subject: Re: NewbieQ: NetBSD and drivers
To: Michael Graff <>
From: Herb Peyerl <>
List: tech-net
Date: 01/18/1996 07:55:55
"Michael Graff" <>  wrote:
 > I can reach about 7.9Mbps over a link with only two computers on it.
 > This is better than SGI Indys can do.  They only get about 7.3Mbps  ;)
 > The reason for the problem is, of course, the collision.  However,
 > turning it off isn't right for two reasons.

When I first got the 3c509 driver working reliably, I started doing 
performance measurements between two identically configured Dell 4/66's
with 3c509's in them on their own custom piece of coax because I was
sure I'd be able to get more than 400kbps... After some tweaking and 
thoughts from Charles/Chris/Theo, I finally got the transfer rate
up to 1010kbps... I didn't think I was going to get much above that so
I stopped there...  I did my measurements with 'ttcp'...

In retrospect, I think it would have been good to continue and attempt to
lower the amount of work the cpu did while maintaining that speed.  I see
now that the driver gets nowhere near 1000kbps as many other fingers have
been in there fixing various things (not to say they didn't need to be