Re: [hatari-devel] Falcon speed

[Eero Tamminen <oak@xxxxxxxxxxxxxx>]

Hi,

On torstai 08 toukokuu 2014, Thomas Bergstrom wrote:
> I use the simple counter method to check CPU consumption.

What exactly you count?


> No DSP, pure 030 with 90-95% running in i-cache or so I guess.
> 
> No, I havn't used the profiler, perhaps it is time. :)

Before optimizing, it's always a good idea to profile
a bit, at least if you're running something where
you aren't familiar with every instruction running. :-)

Basic profiler usage is simple, just do "profile on"
in debugger, continue emulation and get back to debugger.
It profiles code that run between debugger invocations.

Besides "profile counts" and "profile cycles" commands,
I would suggest saving the profiler output for all
instructions with "profile save <file>" to a file and
browsing it in text viewer.


	- Eero

> Br,
> 
> /Thomas
> 
> > How do you measure the CPU consumption on 030?
> > 
> > And is DSP running?
> > 
> > (You could check whether you see same difference with "--dsp none")
> > 
> >> 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.
> > 
> > Have you used Hatari profiler?  That shows how many emulated
> > cycles Hatari spends on each instruction in your code:
> > http://hg.tuxfamily.org/mercurialroot/hatari/hatari/raw-
> > file/tip/doc/manual.html#Profiling
> > 
> > If you see in that output something suspicious, it would be
> > great if you could provide a more isolated use-case demonstrating that.
> > 
> > 	- Eero
> > 	
> >> 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".
> > 
> > ...
> > 
> >>>> 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