> 
> 
> On Fri, 27 Oct 2000, NetBSD Bob wrote:
> 
> > > > on the MVII, even with a stripped to the bare bones 1.5 kernel.  Ethernet
> > > > speeds, for example were 33% faster on the 1.3.2 with generic kernel,
> 
> 4.3tahoe is much faster than 1.4 at least, i havent tried 1.5 on a uvax 
That depends very much what you measure. fork() for example is many times
faster than 4.3BSD.

> yet but from what i see here it would be even slower. I think a lot of 
> this has to do with gcc being a mediocre compiler on the VAX. pcc2 is a 
> very nice compiler, and the only thing that is keeping people here from 
> using it is that most of the code these days is ANSI and not K&R and 
> pcc[2] are k&r compilers. Anybody think it might be worthwhile to modify 
> pcc2 to be ansi compatible and then ditch gcc on the VAX?
> (of course, the best C compiler for the VAX is the DEC vcc, the unix port 
> of the VMS VAX C compiler.. :-)
> 
I beg to differ. VAX is probably the architecture where gcc is best compared
to the native compilers, and the vcc that follows Ultrix at least is more
than bad; both in code generation and buggyness.

To illustrate this I took some time and made a simple benchmark:
On a VAX8800 running Ultrix 4.5 I compiled the AT&T dc with those three
compilers, and made it calculate something that takes time. dc do not
use any library routines for its internal work so the differences
do fairly well mirror the compiler efficiency:

Running the command:
% echo "2 9999 ^ 3 6308 ^ / p" | /usr/bin/time ./dc

gave the following results:

cc:
       44.7 real        44.4 user         0.0 sys

vcc:
       51.0 real        50.8 user         0.0 sys  

gcc:
       31.3 real        31.1 user         0.0 sys  


This shows that there is a huge difference between the efficiency of
those compilers. 
All tests was compiled with -O on the compilers.

-- Ragge