From owner-freebsd-hackers  Thu Jun  8 12:38: 3 2000
Delivered-To: freebsd-hackers@freebsd.org
Received: from verdi.nethelp.no (verdi.nethelp.no [158.36.41.162])
	by hub.freebsd.org (Postfix) with SMTP id 96AC837B681
	for <hackers@FreeBSD.ORG>; Thu,  8 Jun 2000 12:37:59 -0700 (PDT)
	(envelope-from sthaug@nethelp.no)
Received: (qmail 37867 invoked by uid 1001); 8 Jun 2000 19:37:56 +0000 (GMT)
To: jhix@mindspring.com
Cc: hackers@FreeBSD.ORG
Subject: Re: if_dc in v4.0 - Forcing store and forward?
From: sthaug@nethelp.no
In-Reply-To: Your message of "Wed, 07 Jun 2000 22:48:17 -0700"
References: <393F33A1.2AE75730@mindspring.com>
X-Mailer: Mew version 1.05+ on Emacs 19.34.2
Mime-Version: 1.0
Content-Type: Text/Plain; charset=us-ascii
Date: Thu, 08 Jun 2000 21:37:56 +0200
Message-ID: <37865.960493076@verdi.nethelp.no>
Sender: owner-freebsd-hackers@FreeBSD.ORG
Precedence: bulk
X-Loop: FreeBSD.ORG

> > I suspect a generic chipset fault, or some design quirk that we are not
> > working around.  Note that the windoze drivers for these devices put them
> > permanently in store-and-forward mode.  if_de has the exact same problem on
> > all of the systems above.
...
> Store and forward mode introduces a horrible performance hit...  Artesyn
> wouldn't show us the source to their workaround  :-(

It should be noted that I was able to saturate a 100 Mbps Ethernet with
FreeBSD 2.2 and a 21140 based card, using around 56% of the CPU of a
PPro-200. This was done almost exactly three years ago, using the (then)
standard if_de driver. I have no idea whether the card was operating in
store-and-forward mode or not - but the performance was perfectly fine.

Steinar Haug, Nethelp consulting, sthaug@nethelp.no


To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-hackers" in the body of the message