Subject: Re: SCSI vs IDE for RiscBSD (was Re: Installation of RiscBSD on non-standard configuration)
To: Stuart Bell <sabell@ARGONET.CO.UK>
From: Mark Brinicombe <amb@physig4.ph.kcl.ac.uk>
List: port-arm32
Date: 08/13/1996 17:56:26
>The problem with IDE drives on the Risc PC isn't the speed that they can
>deliver, nor the speed of the RPC bus, but, of course, the speed of the
>on-board IDE interface. The Yellowstone RapIDE i/face is now 140ukp inc VAT,
>but is it supported by RiscBSD?

Not yet. This is something that is very frustrating.

YES agreed to loan me a card and provide some basic technical info on the card
way back before Wakefield.

So far nothing has materialised.

As soon as I can get hold of a card and some info I will work on a driver.
Two immediate speed gains without any effort are

1. 32 bit xfers instead of 16 bit
2. no need of the extra code in copy routines to combine/split 16 bit values.

Disc speed / capacity is becoming a serious issue for me when I am regularly
rebuild the entire RiscBSD distribution.
I am currently considering either going for a large scsi (looks like I will
need a 9GB) and writing a very fast SCSI driver (or get Scott to do it)
or going for a number of smaller capacity IDE drives on podule based
interfaces.
(has the advantage of not losing everything if a disc goes down) and writing a
driver for the IDE podule.
Currently the only high performance IDE podule that I know of is the RapIDE ;-(

Think it is about time I make my weekly/fortnightly call to YES.

Cheers,
				Mark


-- 
Mark Brinicombe				amb@physig.ph.kcl.ac.uk
Research Associate			http://www.ph.kcl.ac.uk/~amb/
Department of Physics			tel: 0171 873 2894
King's College London			fax: 0171 873 2716