Re: [hatari-devel] Falcon speed

[laurent.sallafranque@xxxxxxx]

> Disabling them results in a much faster Falcon. Strange that we get so different results

If you say that it's strange that disabling cycle exact and prefetch mode does much different results and when they're enabled, that's normal.
The table of cycles for the new cpu core is applied only for this configuration.

In non cycle exact mode, or non prefetch mode or in MMU mode, each instruction takes 2 cycles (which is wrong of course)


If yo say that what is strange is hatari speed on your machine and on mine, I agree.
I've got a demo that seems to run slower on hatari than on my real falcon (underscore demo if I'm right) (it starts in a tunnel, then, there's a 3d object with motion blur, then, a kind of maze in 3D DSP (that crashs under hatari at the moment).

Except this demo, I always detect that hatari runs faster than my falcon (but I'm running my falcon in VGA, this may change my perception of speed).

Regards

Laurent





----- Mail original -----
De: "Thomas Bergstrom" <tb@xxxxxxxxxxxxx>
À: hatari-devel@xxxxxxxxxxxxxxxxxxx
Envoyé: Mercredi 7 Mai 2014 09:51:55
Objet: Re: [hatari-devel] Falcon speed


Hi,

Hmm. When enabling both cycle exact and prefetch mode I think Hatari is 
close to real Falcon speed. That goes for both my laptops, one AMD A4 and 
one Intel i5. Disabling them results in a much faster Falcon. Strange that 
we get so different results. I have the same configuration as you except 
that I have the blitter emu disabled.

Perhaps my memory is misleading me, I will do some more tests and get 
back. :)

Br,

/Thomas



On Wed, 7 May 2014, laurent.sallafranque@xxxxxxx wrote:d 

> Hi Thomas,
>
> The Falcon emulation is not speed accurate actually, neither cycle accurate.
>
> For example, the current dev version of Racer runs in 3 VBLs under Hatari, whereas it runs in 5 VBLs under my Falcon.
> (Hatari is 2 VBLs faster than the real machine).
>
> On my fast computer, hatari is always faster than my real Falcon (anyway I choose cycle exact, prefetch mode, or not).
>
> The Hatari parameters I use for Falcon emulation are :
>
> CPU : winUAE core (hatari_falcon exe)
>
> CPU Type   : 68030
> CPU clock  : 16 Mhz
> Falcon DSP : Full
>
> CPU parameters :
> 24 bits addressing    : ON
> Prefetch mode, slower : ON
> Cycle exact, slower   : ON
> Real time clock emu   : ON
> Patch Timer_D         : OFF
> Blitter emu           : ON
> MMU emulation         : OFF (except if you need special apps, but MMU emulation is not cycle accurate at all)
>
> FPU : 68882
> More compatible, slower : ON
>
>
> TOS : 4.04 Fr
>
> Memory : 4 or 14 megs
>
>
> The cycle exact mode is the one that allows the most programs to work (but if you use the old CPU core (hatari.exe) in Falcon mode, the timings are again different and some rare programs that don't work with the ne core works with the ols one (like the MOAI96 demo by Mikro)
>
> The MMU emulation CPU interprets all the CPU instructions (MMU, CPU, FPU) in 2 cycles, no matter the instruction.
>
>
> There's still work to do before hatari becomes an accurate Falcon emulator, but it's already useable and quite efficient with many programs ans demos.
>
> Regards
>
> Laurent
>
>
>
> ----- Mail original -----
> De: "Thomas Bergstrom" <tb@xxxxxxxxxxxxx>
> À: hatari-devel@xxxxxxxxxxxxxxxxxxx
> Envoyé: Mercredi 7 Mai 2014 09:05:23
> Objet: [hatari-devel] Falcon speed
>
>
> Hi,
>
> I just wonder if there are any bench figures of Hatari Falcon. I get the
> feeling that if you enable "cycle exact" and "prefetch mode" you get a
> slightly slower Falcon than the real thing. And if you disable those you
> get a CT2 or Nemesis speeded Falcon. Any measurements made?
>
> Just recently joined the list so my appologies if this has been discussed
> alot before...
>
> Br,
>
> /Thomas, New Beat
>
>
>
>
>