RPCS3 PS3 Emulator performance

[LtRoyalShrimp]

Hi All,

I saw this video today: 

 https://www.youtube.com/watch?v=Y6vysVDQJjQ

And it got me thinking: 

How is it possible to emulate a PS3, with its very unique, and powerful(More than a PS4) architecture at such speeds? 

I obviously see the glaring graphical issues and what not, but this is pretty amazing. The PS3 runs on a CELL processor, which is a CPU and 7 co-proccesors. The Game Cube is nowhere near as powerful. 

I also noticed they are using DX12. Would making a DX12 thread for Dolphin have noticeable improvements? Since Dolphin is CPU bound, maybe not? 

If i'm completely off base here, please, im all ears.  

[Zee530]

As long as the console itself uses several CPU cores developing an emulator for it gives you a good chance of further breaking it's processes to more cores and taking advantage of modern hardware, but unfortunately it's not the case for the GC or Wii

[lamedude]

Looking at the simplicity of the game it might not be using only a few or no SPEs.

[DrHouse64]

The PS3 CELL CPU is a special one which have 7 cores instead of 8, and games only have access to 6 cores (the last one is for PS3 OS).

They are clocked at 3.2 GHz so I guess the best way to emulate it is to create a JIT which uses 6 threads in order to decode CELL instructions, one thread by CELL core, so you must have a 6 core Intel/AMD CPU. Man, now that I think about it, PS3 emulation requirements are really heavy.

I wonder if it's possible to process 2 CELL cores in 1 thread at full speed, so the JIT only needs 3 cores of your PC CPU. I don't know how RPCS3 handle it. Not to mention the GPU part.

[LtRoyalShrimp]

(12-19-2015, 01:32 AM)DrHouse64 Wrote: The PS3 CELL CPU is a special one which have 7 cores instead of 8, and games only have access to 6 cores (the last one is for PS3 OS).

They are clocked at 3.2 GHz so I guess the best way to emulate it is to create a JIT which uses 6 threads in order to decode CELL instructions, one thread by CELL core, so you must have a 6 core Intel/AMD CPU. Man, now that I think about it, PS3 emulation requirements are really heavy.

I wonder if it's possible to process 2 CELL cores in 1 thread at full speed, so the JIT only needs 3 cores of your PC CPU. I don't know how RPCS3 handle it. Not to mention the GPU part.

Dig through the code, its on Github. I would to, but I'm not a programmer.  

[KHRZ]

Most of the graphics is just handled wit DX12 calls. That game doesn't look complicated enough to need much CPU performance, I would guess most of the PS3 CPU cores are mostly idle.

[DrHouse64]

My bad. The CELL actually have 1 Power PC core @3.2 Ghz that delegates tasks to 8 SIMD SPE cores (6 for the game, 1 for PS3 OS and 1 unused / backup core). Still, it's a huge task.

[Link_to_the_past]

(12-18-2015, 08:50 PM)LtRoyalShrimp Wrote: Hi All,

I saw this video today: 

 https://www.youtube.com/watch?v=Y6vysVDQJjQ

And it got me thinking: 

How is it possible to emulate a PS3, with its very unique, and powerful(More than a PS4) architecture at such speeds? 

I obviously see the glaring graphical issues and what not, but this is pretty amazing. The PS3 runs on a CELL processor, which is a CPU and 7 co-proccesors. The Game Cube is nowhere near as powerful. 

I also noticed they are using DX12. Would making a DX12 thread for Dolphin have noticeable improvements? Since Dolphin is CPU bound, maybe not? 

If i'm completely off base here, please, im all ears.  

Well he is using an Intel Core i7 6700K @ 4.60 Ghz and he can't get full speed all times in a lightweight game. There are lightweight games in dolphin currently that can run 10x normal speed ingame with that cpu overclocked. So you can say that ps3 emulation is at the very least 10 times more demanding than wii - gamecube emulation. While the above is a pretty vague and general estimation people tend to forget how fast dolphin runs in a top of the line cpu due to the framelimiter being used (and shader generation frame dips giving the impression of higher power needs).

Edit: Here is a pic of Phantom Brave for wii ingame (a game similar to Disgaea) at 900% speed in dolphin using my now old and cosiderably less powerful 2500k at 4,1 ghz.

http://prntscr.com/9frxdf

[DrHouse64]

900% speed huh. 2015 for Dolphin is like 2005 was for N64 emulation.

[Emulator_Team]

https://www.youtube.com/watch?v=uJ_Q5eKxdno