On Sep 24,  5:48pm, michel beausejour wrote:
> Under NetBSD i've compiled the program with gcc with options -m68040 and -m68881
> under FreeBSD i've used the options -m486.

  Which gcc compiler were you using?  Also, is gcc going to use
68040-specific library routines for the unimplimented instructions, or
use the 68881 instructions and take exceptions for all the unimplimented
instructions?

> NetBSD                                                    FreeBSD 2.0.5
> A3000 2meg chip/8megsFAST                             Dell 486Dx33 12megs (70ns) 
> (8megs SCZIP 70ns)
> PicassoII 
> A3640 (68040 25MHZ)

  The A3640 in an A3000 probably isn't going to perform very well.  I
assume it is using the A3000 motherboard memory and memory access is
going to be limited by the A3000 design.

> A3000 (040) running amigados         povray said that it took 12mins to render
> A3000 (040) running NetBSD-current   " " " "" " "" " " "" " ""18mins to render
> Dell 486DX33 running FreeBSD-2.0.5                             9mins to render

  A2000/Zeus (33Mhz 040) NetBSD-current                        8.5mins

> How come the big difference between NetBSD and FreeBSD i thought that  they will be
> closer than that. No?
...
> It may look like that i'm comparing apples with oranges but i disagree.

  I suspect you are - my guess is that a 25Mhz 68040 in an A3000 without
any local memory is going to perform much poorer than a 486Dx33.  My
33Mhz Zeus, which has local memory on the accelerator, appears to
perform comparably with the 486Dx33.  I also noticed that when povray
was running, I was getting about 55% user/45% system to 70% user/30%
system time.  I suspect this is due to the executable using 68881
instructions, causing a high trap rate to the 68040 FPSP emulation
routines.  I haven't figured out if there is a way to use a
68040-specific math library yet.  That may help a little bit.  I would
hope that the AmigaDOS version of povray would have been compiled with
68040-specific libraries to eliminate the unimplemented instruction
execptions.

Michael