Re: [hatari-devel] Falcon speed

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Hi,

The measurement is CPU Load of the 68030. CPU usage per game frame.
I just found it strange that my and Laurent's experiences was so different. In Laurent's case, Hatari is always faster than a Falcon but in my case it is 30% slower when enabling Cycle Exact and Prefetch mode which makes it a bit hard to know how much work can be put on the CPU and still keep the frame rate on a real Falcon.
I was curious to hear other peoples experiences regarding this. I use Hatari alot and think it's fantastic, just have to find a way to deal with this "problem". 

Br,

/Thomas


On Thu, 8 May 2014, Eero Tamminen wrote:


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

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