On Sat Jan 13 2001 at 13:51:47 +0100, T@W wrote:
> Hi folks,
> The info about the DUMMY_NOPS option confuses me:is it eliminated by
> commenting or commenting out??
> 
> # eliminate delay no-ops in I/O; recommended on all but very old machines
> #options 	DUMMY_NOPS
> 
> or
> 
> # eliminate delay no-ops in I/O; recommended on all but very old machines
> options 	DUMMY_NOPS

reading sys/arch/i386/i386/locore.s:

#ifdef DUMMY_NOPS       /* this will break some older machines */
#define FASTER_NOP
#define NOP
#else
#define FASTER_NOP      pushl %eax ; inb $0x84,%al ; popl %eax
#define NOP     pushl %eax ; inb $0x84,%al ; inb $0x84,%al ; popl %eax
#endif

So defining DUMMY_NOPS is the way to go for maximal speed.  Yes, the
naming is very confusing ..

HTH, HAND
  pooka 

-- 
Antti Kantee <pooka@iki.fi>          v          Of course he runs NetBSD
http://www.iki.fi/pooka/             i            http://www.NetBSD.org/