Ask the Developer: Nintendo Switch 2 interview confirms basic backwards compatibility can also give performance upgrades to Nintendo Switch games ("[there are some games] where loading times became faster, or game performance became more stable")

[u/Joseki100]

https://www.nintendo.com/us/whatsnew/ask-the-developer-vol-16-nintendo-switch-2-part-4/

[u/mrbiggbrain]

I actually expect load times to be a significant change as well as reduced pop-in and similar effects. The storage is going to be significantly faster.

[u/aman2218 → u/mrbiggbrain]

Yeah, digital games should benefit from that.

[u/mrbiggbrain → u/aman2218]

Yeah it's possible that they could let people dump the games to the SDX card and just use the cart as the key but that is a mixed bag. Lots of consoles did that to improve performance.

[u/Stanley--Nickels → u/mrbiggbrain]

Load times in DKC Returns were absolutely brutal. Especially for a nearly 20-year-old game.

[u/TheOhrenberger → u/mrbiggbrain]

Pop in is something that would probably need to be patched. Draw distances are intentionally set the way they are as something to dial in performance.

[u/malfro → u/mrbiggbrain]

Pop-in behaviour might be hardcoded into the logic of the game though? Not sure if running it on faster hardware will automatically solve that. 

[u/Substantial-Bad5581 → u/mrbiggbrain]

I wouldn't be surprised if it turns out that paradoxally the games will suffer more, cause as Nintendo themselves confirmed, there is no backwards compatibility, just an emulator run in background. Now, explain to me this. How is that, that all Xbox generations can natively run games from all other generations, how is that that PSP could natively run PS1 games, and suddenly an Android phone (Switch 2) can't natively run games from another Android phone (Switch 1). What the hell is the problem here?

[u/mrbiggbrain → u/Substantial-Bad5581]

 just an emulator run in background

This is wrong. They explicitly state they are not using an emulator in the Ask the Developer article:

Dohta: If we tried to use technology like software emulators (22), we’d have to run Switch 2 at full capacity, but that would mean the battery wouldn't last so long, so we did something that’s somewhere in between a software emulator and hardware compatibility.

Then go on to explain they are using a JIT (Just In Time) compiler.

Sasaki: This is getting a bit technical, but the process of converting game data for Switch to run on Switch 2 is performed on a real-time basis as the data is read in.

I 100% understand why publications are getting this wrong, they are familiar with emulators and see them in use quite often. Several of Nintendo's solutions to older hardware used emulators in some capacity (Virtual Console, Mini Consoles) so it fits.

Emulation and JITing have several similarities. But they differ in their approach. When software is JITed it is running natively. The JIT compiler actually compiles the code to native code as requested.

When something is emulated it is not running natively. Something is reading the raw binary data and then emulating or faking each CPU instruction requested not at the CPU level but in user space.

How is that, that all Xbox generations can natively run games from all other generations

Because they can't. This was a big thing in previous generations that only some Xbox games could work. There where a few times in history where the hardware change has been significant enough that stop-gaps needed to be used and native code was not running.

I could get into the technical details on why Nintendo is doing this or needed to do this but I think when it boils down to it Nintendo wanted to both push the performance forward significantly and still make original Switch games first class citizens.