On Wed, Nov 22, 2000 at 09:49:42PM +0100, Hauke Fath wrote:
> Transition from vanilla to A/UX interrupt mode? I feel that at the time,
> SCSI performance on my Quadra 700 dropped significantly.

Ouch.  That should not have hurt performance at all.  Were you running
ethernet, serial, or anything else while running bonnie?

> - These figures may in part be distorted due to loss of clock ticks, but by
> an order of magnitude? Unfortunately, I do not have older figures from the
> Quadra 700.

With the A/UX interrupt layout, you should not be losing as many clock
ticks.  However, clock ticks, ADB, ethernet, and serial interrupts can
supercede SCSI interrupts in the A/UX scheme.  Except that the esp
driver goes to splhigh while running (because a serial interrupt could
interfere with the SCSI transfer).

If you want to try it without A/UX interrupts, you just need to change
line 2166 of machdep.c (netbsd-current, 2170 in NetBSD-1.5) where it reads:
	mac68k_machine.aux_interrupts = 1;

Change that 1 to a 0, and it should not use the A/UX interrupt scheme
at all.  If you try this, please let me know if you see much of a
difference!  I won't have a chance to try it for a little while.

-allen