Subject: Re: DMA
To: Mauricio Tavares <raub@kushana.aero.ufl.edu>
From: Jason Thorpe <thorpej@nas.nasa.gov>
List: port-sun3
Date: 01/14/1996 10:13:12
On Sat, 13 Jan 1996 23:43:41 -0500 (EST) 
 raub@kushana.aero.ufl.edu (Mauricio Tavares) wrote:

 > 	Where was I?  Oh, yes.  So I now have a 1GB SCSI2 drive attached
 > to the 3/50 replacing the CDC 96141-155.  Currently, it takes quite a lot
 > of time to access the drive; for some reason it reminds me of a C64. 
 > Would enabling the DMA "mode" speed up this drive so that I will be able
 > to load X in my lifetime? 

Definitely.  I noticed _AMAZING_ performance improvements when I did this 
on my 3/60.  Spin-waiting around a PIO transfer is ... horrifying :-)

 > 	In an unrelated topic, how do you rebuild the kernel in NetBSD?  
 > In ultrix we had this /usr/sys directory where the kernel config file 
 > would be hidden.  Would NetBSD have something similar?

cd /usr/src/sys/arch/sun3/conf
cp GENERIC PICKLE
vi PICKLE <change to your liking>
config PICKLE
cd ../compile/PICKLE
make depend && make

Whee!  :-)

--------------------------------------------------------------------------
Jason R. Thorpe                                       thorpej@nas.nasa.gov
NASA Ames Research Center                               Home: 408.866.1912
NAS: M/S 258-6                                          Work: 415.604.0935
Moffett Field, CA 94035                                Pager: 415.428.6939