Pi Zero so slow it does't even run NES at full speed

[Sage Freke]

As the title says: I read a million of times that the Pi Zero can run Mega Drive and even many SNES games, but in my experience not even NES games run at full speed: I made some tests and I get 41/42fps in Alien Syndrome (and around 53 in sidescrollers like Castlevania).

By disabling shaders I get a boost of 3fps (44/45 instead of 41/42).

Initially I set the rendering resolution to 320x240 and the output res 1280x720, I didn't know that shaders look awful in 240p though, so I raised the internal res to 640x480 and the output one to 1080p.

However, I didn't notice any significative difference in performances, the games always run at 40/50fps (and with crackling music) at any resolution that I tried (which are the 4 that I mentioned above).

P.S. when I'm inside retroarch's menu the game runs at full 60 and sometimes it keeps the 60 when I exit from the menu, but after 20/30 seconds the framerate starts to drop and ultimately stabilizes at 41/42

P.P.S. I also get phantom inputs on the Emulation Station menu, but not in games, so I didn't try too much to solve the problem (also because from what I read it seems very hard, if not impossible, to get rid of it).

Pi model: Pi Zero
Power Supply used: Aukru branded RPi PSU rated 3A
RetroPie Version: 4.7.1 Last Commit: in the future (c7080175)
Built from: retropie-buster-4.7.1-rpi1_zero.img
USB devices: none (aside from the controller)
Controller: generic NES USB replica connected through OTG cable
Emulator: NES (lr-fceumm)

[dankcushions]

@sage-freke verbose log, please, as per https://retropie.org.uk/forum/topic/3/read-this-first

[Sage Freke]

@dankcushions I did read it thoroughly (as you can see from the info at the bottom of my post).
It says "Verbose log (if relevant)", but since I didn't get any error I didn't think it was relevant.

However, I had to reinstall everything on a new SD card because the old one was flaky, this time though I left lr-quicknes as the default emulator and games do run at 60.

I had previously chosen lr-fceumm because I read it was more accurate but I didn't know it was also that demanding.

P.S. after further research I found out that lr-fceumm is notoriously slow (while the post that convinced me to select it stated the opposite: nestopia should have been the slow one. Oh well, at lest this post could be useful to someone that has the same problem).

[barbudreadmon]

@sage-freke said in Pi Zero so slow it does't even run NES at full speed:

I read a million of times that the Pi Zero can run Mega Drive and even many SNES games

Your understanding that a nes emulator would necessarily be faster than a snes emulator is wrong, it mostly depends on how accurate the emulator will be. You can't use accurate emulators on a pi0, it's way too underpowered (fceumm only succeed ~45% of nes accuracy tests, and it's already way too slow; for reference, nestopia ~85% and mesen 100%), meaning you'll always have a sub-optimal emulation experience (less accurate means more bugs, whether they will be easily noticeable or not), which is why you should only consider buying a pi0 if you don't have any other choice (DIY handheld project)

[Sage Freke]

@barbudreadmon I understand now, thanks for the explanation, I got the wrong impression by reading stuff online.

I had the Pi Zero laying around and I just thought of putting it inside a NES controller.

[barbudreadmon]

@sage-freke said in Pi Zero so slow it does't even run NES at full speed:

putting it inside a NES controller

Yeah, that's the kind of DIY project where you would want a pi0, does it fit though ? I don't remember my nes controllers having lots of spare room.

[Sage Freke]

@barbudreadmon It should fit by cutting something here and there (don't worry, I'm not using an original NES controller), but I'm not at that stage yet, I want to set the software side first.

Although, after a bit of playtesting I'm starting to have second thoughts: the NES d-pad is tiny and very close to the left edge of the controller, I'm having trouble going up and down in a straight line (I never used one before so I didn't know what to expect).
I may end up using a SNES controller, I have some retro-bit replicas laying around.

[Capeman]

Make sure you’re using the fastest emulator for slower hardware. If you’re running Fceumm on a pi zero you definitely won’t get full speed, but nestopia runs just fine.

[dankcushions]

@capeman lr-quicknes is the fastest. it’s the default for pi0/1.

[barbudreadmon]

@capeman said in Pi Zero so slow it does't even run NES at full speed:

If you’re running Fceumm on a pi zero you definitely won’t get full speed, but nestopia runs just fine.

nestopia run about 30% slower than fceumm on my computer, so i can't imagine how it could run fine on a pi0 if fceumm doesn't

[Sage Freke]

@barbudreadmon I tried nestopia and I gained 10fps in Alien Syndrome (from 40 to 50, still not playable though) but Castlevania runs a little slower this time: 49 instead of 53. I'll keep using lr-quicknes.

[barbudreadmon]

@sage-freke Weird, on my computer nestopia is slower on Alien Syndrome, but yeah there could be discrepancies between games since they use hundreds of different mappers (some kind of special chip in nes cartridges, with different levels of complexity, the emulator needs to emulate it)

[DynaMight]

Try flashing RetroPie 4.3 instead. It runs loads faster on the Pi0 as its not as bloated since the newer versions that are more concentrated on the newer, way more, powerful Pi's.

4.3 still feels like the latest RetroPie with most of the ES features with themes etc but everything is a lot lighter on resources.

I still had to change MegaDrive to the Picodrive core though for full speed MD.

[dankcushions]

@dynamight picodrive has always been the default megadrive emulator for pi 1/0. pi1/0 versions of retropie don't really have any emulators/software related to other pi models installed by default. that's why there's different image downloads.

emulators can increase in accuracy and requirements, but the ancient versions used for pi1/0 shouldn't.