Subject: Re: DEFZA-AA
To: Jochen Kunz <>
From: Matt Thomas <>
List: port-alpha
Date: 06/09/2002 14:21:39
At 02:02 PM 6/9/2002, Jochen Kunz wrote:
>On 2002.06.09 21:46 Robert Schaefer wrote:
> > There are some google hits on port-pmax that indicated ~40Mb/s
> > is all you'll see with a DEFTA, being as it's an older card.
>I know that, read it all... But I don't trust that ttcp measurements
>much, as this numbers weren't taken by me. ;-)
>Only 40MBit/s sounds a bit to low for my taste. I can not beleave that
>DEC made that thing so slow. The SGI is of the same vintage and gets a
>bit more then 80MBit/s easyly. I mean. DEC is a synonym for exelent IO

That's why they made the DEFTA. :)  The DEFZA is PIO for transmit and
that significantly reduces the transmit throughput.  Receive is DMA

I have the DEFZA docs.  Some things are a bit strange about it.  SMT
packets need to be looped back to the onboard 68k to be processed.

> > [OT: OpenVMS _does_ support the DEFZA, doesn't it?]
>I am no VMS head, but Tru64 5.1 still supports the DEFZA. So I think
>your chances are good.

OpenVMS does support the DEFZA.

Matt Thomas               Internet:
3am Software Foundry      WWW URL:
Cupertino, CA             Disclaimer: I avow all knowledge of this message