Why EXACTLY is PS2 emulation so "unachievable"?

[MrChops]

Here's the PS2 thread. I mean this one slightly more serious than the xbox 360 thread.

Portable ps2 emulation is the holy grail of handhelds for me. I got interested in Pandora back when it was just an idea, I was trying to find a portable ps2 solution, so I bought a ps2 slim and attached a screen and a couple portable dvd batteries to it and had some fun. I quickly wanted a more portable solution and looked into the ben heck custom mods and had dreams of going down that path. Then I learned of dual core x86 netbooks coming out and had hopes that ps2 emu was possible that way, which was obviously wishful thinking. Then I found the gp32x.de forums and started to understand just how hard it was to emulate modern game counsels and how awesome the pandora was going to be compared to other handhelds at the time.  

My hope is that in the near future with modern arm soc's coming out, that portable ps2 could become a reality. I am no dev or hardware guy so my hopes are completely based on speculation and the small amount of research I've done so please be easy on me.

Pcsx2 is the emu which is predominantly used to emulate ps2 on the pc today. The software is open source and has a linux port as detailed here: http://pcsx2.net/download.html

There appears to be some work done to port this to arm already. See here:

https://code.google.com/p/pcsx2/source/browse/trunk/3rdparty/SDL-1.3.0-5387/Android.mk?r=4337

https://code.google.com/p/pcsx2/source/browse/trunk/3rdparty/SDL-1.3.0-5387/README.android?r=4337

I have no idea how much has been done and it's for android but for the purposes of this thread I'd like to concede to the fact that for a ps2 emulator to make it to a usable, portable arm format that an ass-ton of programming would be required from highly intelligent and motivated people. I'd like the focus of this thread to be about the feasibility of portable ps2 emulation on arm soc in the near-ish future as pertains to advances in hardware. 

Here is a thread detailing the minimum system requirements including gpu for pcsx2:

http://forums.ngemu.com/showthread.php?t=92946

And the specs for the graphics card specified:

http://www.nvidia.com/object/go_7_series_techspecs.html

Here is the recommended system requirements including gpu for pcsx2:   

http://forums.ngemu.com/showthread.php?t=92946

and the specs for the graphics card specified:

http://www.geforce.com/hardware/desktop-gpus/geforce-8800-gt/specifications

Now, I know there is much more than comparing specs and mhz between x86 and arm however,  hopefully there is some conclusions to be made with such comparisons. To that end, here is the info I could find about the newest soc which may be best situated to make my portable ps2 dreams come true:

http://www.nvidia.com/object/tegra-4-processor.html

http://forum.xda-developers.com/showthread.php?t=2087129

Granted that the amount of tegra 4 specs are lacking and no one really knows how a ps2 emu will work on modern socs until someone ports and optimizes it. However, I'd be very interested in hearing the opinions of our devs and hardware guys as to the possibility of using the tegra 4 or any other new arm soc for ps2 emulation..  

If the current socs have no chance, why and what will need to happen to make it possible? How long do you think we are looking at to get portable ps2 action?

 

[2bit]

Well ... to my knowledge ( I probably know less about coding and hardware then you so my opinion here is worth 1/8th used potato ) but to my knowledge the ps2 was weaker than GameCube graphics wise . We now have a ps2 port to 3ds ( metal gear solid : snake eater ) and Considering how after 2 hours of my 3ds' battery this nearly drains my 3ds battery I'm assuming it has to do with resource consumption and optimization . Would the pandora even have enough of the all important RAM to throw at it ?


Remember the situation with n64 if we can't get it PERFECT yet what implies ps2 ?

 

[apersonthinks]

Here's the PS2 thread. I mean this one slightly more serious than the xbox 360 thread.

Portable ps2 emulation is the holy grail of handhelds for me. I got interested in Pandora back when it was just an idea, I was trying to find a portable ps2 solution, so I bought a ps2 slim and attached a screen and a couple portable dvd batteries to it and had some fun. I quickly wanted a more portable solution and looked into the ben heck custom mods and had dreams of going down that path. Then I learned of dual core x86 netbooks coming out and had hopes that ps2 emu was possible that way, which was obviously wishful thinking. Then I found the gp32x.de forums and started to understand just how hard it was to emulate modern game counsels and how awesome the pandora was going to be compared to other handhelds at the time.  

My hope is that in the near future with modern arm soc's coming out, that portable ps2 could become a reality. I am no dev or hardware guy so my hopes are completely based on speculation and the small amount of research I've done so please be easy on me.

Pcsx2 is the emu which is predominantly used to emulate ps2 on the pc today. The software is open source and has a linux port as detailed here: http://pcsx2.net/download.html

There appears to be some work done to port this to arm already. See here:

https://code.google.com/p/pcsx2/source/browse/trunk/3rdparty/SDL-1.3.0-5387/Android.mk?r=4337

https://code.google.com/p/pcsx2/source/browse/trunk/3rdparty/SDL-1.3.0-5387/README.android?r=4337

I have no idea how much has been done and it's for android but for the purposes of this thread I'd like to concede to the fact that for a ps2 emulator to make it to a usable, portable arm format that an ass-ton of programming would be required from highly intelligent and motivated people. I'd like the focus of this thread to be about the feasibility of portable ps2 emulation on arm soc in the near-ish future as pertains to advances in hardware. 

Here is a thread detailing the minimum system requirements including gpu for pcsx2:

http://forums.ngemu.com/showthread.php?t=92946

And the specs for the graphics card specified:

http://www.nvidia.com/object/go_7_series_techspecs.html

Here is the recommended system requirements including gpu for pcsx2:   

http://forums.ngemu.com/showthread.php?t=92946

and the specs for the graphics card specified:

http://www.geforce.com/hardware/desktop-gpus/geforce-8800-gt/specifications

Now, I know there is much more than comparing specs and mhz between x86 and arm however,  hopefully there is some conclusions to be made with such comparisons. To that end, here is the info I could find about the newest soc which may be best situated to make my portable ps2 dreams come true:

http://www.nvidia.com/object/tegra-4-processor.html

http://forum.xda-developers.com/showthread.php?t=2087129

Granted that the amount of tegra 4 specs are lacking and no one really knows how a ps2 emu will work on modern socs until someone ports and optimizes it. However, I'd be very interested in hearing the opinions of our devs and hardware guys as to the possibility of using the tegra 4 or any other new arm soc for ps2 emulation..  

If the current socs have no chance, why and what will need to happen to make it possible? How long do you think we are looking at to get portable ps2 action?

Please note: an Android.mk fail in a source does NOT mean an arm/android port at all. As pcsx2 uses SDL 1.3, and SDL 1.3 has native android support, an Android.mk file is included. As this is the ONLY folder in the source that has an Android.mk file, SDL would compile for android and that's it. (I've had to explain this on multiple forums multiple times and its starting to bug me )

 

[ekianjo]

Well ... to my knowledge ( I probably know less about coding and hardware then you so my opinion here is worth 1/8th used potato ) but to my knowledge the ps2 was weaker than GameCube graphics wise . We now have a ps2 port to 3ds ( metal gear solid : snake eater ) and Considering how after 2 hours of my 3ds' battery this nearly drains my 3ds battery I'm assuming it has to do with resource consumption and optimization . Would the pandora even have enough of the all important RAM to throw at it ?


Remember the situation with n64 if we can't get it PERFECT yet what implies ps2 ?

It's not about how powerful the hardware is, it's about how complicated its inner workings are. Look at the Amiga - it's a "low-power" hardware by today standards, but still a challenging system to emulate because of the numerous interactions between the co-processors to display stuff on screen. 

 

[bismuthdrummer]

Well maybe if you guys stopped burning through the Exophase Bait™ so fast, we'd get some answers! But I think his answers here would play out at least somewhat similar to his answer to Seeeejaaaay. GC and PS2 are from the same generation.

I'm guessing he'd make an appeal to common sense by comparison of performance at a high level. Look at what kind of desktop/laptop is required to run PCSX2. The minimum requirements state explicitly that "most games will be unplayably slow", meaning that they're there for an architectural minimum and perhaps a laugh at how much faster you'd need to go to have fun. So to emulate in any worthwhile fashion you'd need to have at least as performant as a Core 2 Duo @ 3.2 GHz or an iCore @ 2.8 GHz.... is Tegra 4 really going to come close to that in any kind of performance metric? And that's before we talk about comparing it to a nVidia 8800gt on the graphics side, or memory bandwidth, or I-have-no-idea-what-else. I'm not a hardware guy for the record, but simple experience gives me skepticism.

There's also the reality that more often than not developers want to port to a device that would meet their minimum expectations for the app that they're porting. So until we have a device whose specs really shine close to what is necessary, I can't see why anyone would bother with making a device emulate a system at slideshow speed, only then to optimize it into a slightly faster slideshow.

That said, of course the time will come when we will be able to emulate PS2, it's just the question of when. I'd also be happy to hear Exo's or any other knowledgeable dev's thoughts on the speculation of timing.

 

[Exophase]

But I think his answers here would play out at least somewhat similar to his answer to Seeeejaaaay. GC and PS2 are from the same generation.

Yeah, more or less. Of course, that thread was about Gamecube on Pandora, while this thread is about PS2 on something hypothetical that sounds much more powerful. I don't really feel confident or comfortable giving much of an estimation for what you'd need for PS2, since I haven't come anywhere close to working on something like this. You can study the system's design and capabilities really carefully but what games actually do drives things really hard. The best we can really do right now is infer results from PCSX2, which I think has had a pretty good optimization over the years, based on the articles I've read on it.

PS2 vs Gamecube is (very very roughly, don't take this too seriously please) sort of like Saturn vs N64. The former is weaker but more complex than the latter. More processors running simultaneously, more esoteric features that have a higher overhead in emulating, at least when you look at the conventional HLE approaches used for N64. Some of that applies to Gamecube emulation as well, since HLE is often used for audio there.

As an example, Gamecube has a CPU with limited SIMD capabilities. No integer SIMD at all and only 2xFP32 floating point SIMD (so-called "paired singles"). For the most part this can be translated to VFP + NEON pretty comfortably. Even the register file size is close enough to that you probably don't really have to worry about register allocation. There's some stuff with fixed point conversion on loads and stores that could be expensive if you have to do it dynamically for every instruction, but if the setup for these quantization modes doesn't change much (such that you can make it a compile-time sort of thing) then the cost won't be too bad.

It also has a hardware T&L engine, but since that's at a higher level specification you can do a more efficient emulation of it.

Compare with PS2, which has 128-bit integer SIMD on its CPU, and two vector coprocessors that perform dual-issue operations over 32 128-bit FP registers. It has a bunch of features like broadcasts, implicit accumulators, horizontal operations, full divisions and sqrts, transcendental operations, random numbers and clipping acceleration that could make it more expensive to emulate. Plus it doesn't handle infinities, NaNs, and dynamic range like IEEE754 which can cause big problems. And it lacks interlocks on some things which makes it really hard to emulate right/efficiently in some cases.. you can see some headaches here: http://forums.pcsx2.net/Thread-blog-PS2-VU-Vector-Unit-Documentation-Part-1


To even get something that works on fast PCs you basically need some to make some assumptions, hacks, and heuristics.. but there's still a fair amount of overhead baked in.

PS2 emulation also needs emulation of the PS1 CPU which handles I/O, although this is probably not a huge deal, especially if it's not used very heavily.

 

[squaresosig]

The ps2 has a complex architecture that makes it very difficult to emulate (Sony may have done that on purpose after what happened with bleem), so right now even powerful computers cannot emulate it that effectively. i have a fast 6 core and a 7970 and can only just play the thing well, and even then its a tad laggy, so until we get a Pandora with 12 cores and the graphics performance of a 7990, or someone optimizes the hell out of pcsx2, ps2 emulation wont be much more than a gimmick for more than just the pandora 

 

[EssoAir]

Is this thread a joke? Because a while ago I made q thread with the exact same title, it just said "Gamecube" instead of "PS2"

 

[Exophase]

No it's not a joke, did you read the post rather than just the title?

 

[monstercameron]

no dev and cant talk about if it would run on a tegra 4 or similarly powerful hardware but currently it seems that a 17W cpu/apu (ivybridge/trinity) could emulate pcsx2 for non-intensive games (older/2d). I would say the lowest power part for "running" pcsx2 on is the (not yet released) amd a6-1450 apu -which is >9W. For the time being, seeing as though we not be able to answer that question here is gamecube/wii [dolphin] emulator running on android https://play.google.com/store/apps/details?id=org.dolphinemu.dolphinemu&referrer=utm_source%3Dappbrain%26utm_medium%3Dappbrain_web%26utm_campaign%3Dappbrain_web

https://www.youtube.com/embed/26a68SslyRU?feature=oembed

http://forums.dolphin-emu.org/Thread-green-notice-development-thread-donations-for-dolphin-android-development

 

[Exophase]

Sorry monstercameron, your A6-1450 comes nowhere even remotely close to a 17W Ivy Bridge i7 in the single-threaded performance crucial for performance for PCSX2. It probably won't even come remotely close to the Trinity you mentioned.

 

[ekianjo]

Our best hope for PS2-like games is with PSP emulation at this point. There were a number of PS2 titles converted to it which were fairly close to the original ones (this being said the PSP is way less powerful, 3d wise, than the PS2, and it shows.). 

PS2 emulation on portable hardware, not before another 3-5 years, and I may be optimistic still. 

 

[monstercameron]

Sorry monstercameron, your A6-1450 comes nowhere even remotely close to a 17W Ivy Bridge i7 in the single-threaded performance crucial for performance for PCSX2. It probably won't even come remotely close to the Trinity you mentioned.

true, but thats is why I added "running" besides my c-50 "runs" pcsx2

https://www.youtube.com/embed/1y0BCIirDhc?feature=oembed
skip to 41 mins

 

[Exophase]

I'm going to be straight up with you.. I've talked to a ton of people over the years who wanted to prove to me that emulator X runs "good enough" or "playable" on platform Y. This is totally subjective and can mean anything, everyone is going to have some different opinion on this, and it could pretty much extend to the very slowest emulation you can imagine. It's just not worth talking about. Post videos if you want, if you really must talk about some kind of performance percentage, but don't expect any kind of meaningful conversation around "runs" (I'd totally double quote that if it didn't look ridiculous)

I will say this - you could make that 60% faster like A6-1450 might, or twice as fast really, and there's still no way in hell that I'm going to play it. If you want to, knock yourself out.

Seriously though don't let me get in the way of you mentioning Temash in every post you ever make

 

[monstercameron]

you have to be so combative everytime my opinion differs from yours? If that is/will be the case then I wont bother you again, I am sorry.

 

[Exophase]

Please explain to me how you feel I was being combative. Unless it's that Temash comment. Which I put a smiley at the end of. But seriously, you do promote Temash a LOT.

This isn't the first time you've been like this. And I hope you realize that when you start judging my intentions towards you it's you who is making things personal. Are you trying to guilt me into never again saying anything contrary to what you post? Because that's not happening. Ever. I suggest you get some thicker skin.

 

[Franko]

........(screeches into the room)....Hey, if you two can't find some sort of common ground here then I'm just going to have to turn on this firehose==D  - -  . .

I stole Binky's keys when he was asleep and now I'm sheriff...er, Moderator.  So lets see some shaking of hands and acknowledgment that Exo has a big brain and that Cameron respects that but just wants to learn and have a pleasant dialogue and exchange with Exo.  Sort of like colleagues, but without the annoying Christmas parties and phone calls...jeeesh, he's really pushing for this here.  Exo, just be YOU.  Don't ever change.

Not that a few thousand Pandora owners and fans aren't thinking the same thing - don't overtax that guy's mind.  Bless you, Exophase.  Thanks for your personal sacrifices and efforts and love towards this project.  You improve and continue to improve a device that awes me.  What a great community we have.

 

[monstercameron]

...don't overtax that guy's mind...

what does that mean?

 

[Franko]

...don't overtax that guy's mind...

what does that mean?

That people might bug me if I talk too long to him.  I'm almost intimidated by the guy's knowledge.  I don't want to waste his precious moments reading my drivel.  THAT's what I mean..


Edit 1:  I didn't direct that at you - I directed it (or so I thought) at myself.  I'm, self-effacing.  I would rather see you and Exo get along....maybe he is stilled miffed about the time that you and him went to that Dairy Queen and you got more sprinkles on your cone.  I have my ideas, but who the fawk cares?  I do enjoy your occasional  technology news dumps on certain pages.  I learn a lot of stuff from you Cameron...don't go away mad...  LOL....was just remembering a Motley Crue song.  PEACE, Cameron.  Keep keeping us all updated - I love it.  You're cool.

 

[ShleeDragon]

Not a single piece of the puzzle is build with ARM in mind.