Re: [hatari-devel] Falcon speed

[Eero Tamminen <oak@xxxxxxxxxxxxxx>]

Hi,

On torstai 08 toukokuu 2014, Thomas Bergstrom wrote:
> Back again after doing some homework.
> 
> I started a game at the same level without playing anything, so these are
> game "idle" CPU Load numbers:
> 
> Machine			CPU Load
> --------------------------------
> Falcon			58.05%
> Hatari, CE&PFM Disabled	41.61%
> Hatari, CE&PFM Enabled	76.51%

Are you measuring Hatari's CPU usage, or running game under MiNT
in Hatari and using e.g. "top" to see your game's CPU usage under MiNT?

If you're measuring Hatari's CPU usage, more accurate emulation
needing more CPU "works as expected".

	- Eero

> Tried on both laptops, both give the exact same numbers. As you can see
> Cycle Exact and Prefetch Mode slows Hatari down to be quite alot slower
> than the real thing. The Hatari version I was running was built Jan 2:nd.
> 
> I run the windows version, maybe the difference is in Windows vs. Linux?
> 
> Perhaps it's the data cache but would that really have that much impact?
> 
> Get the feeling that there is some option/setup that's missing or so.
> 
> Br,
> 
> /Thomas
> 
> On Wed, 7 May 2014, Eero Tamminen wrote:
> > Hi,
> > 
> > Hatari WinUAE CPU core doesn't emulate 030 data cache.
> > 
> > According to comments by Douglas about his experience
> > on optimization things related to that in Bad Mood, code
> > using data cache well works faster on real Falcon than
> > in Hatari.
> > 
> > 	- Eero
> > 
> > On keskiviikko 07 toukokuu 2014, laurent.sallafranque@xxxxxxx wrote:
> >>> 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