Any Difference in performance using 0/1 img on Pi 3B+

maxrpg

Hi all,

I've been using retropie on my zero for about 6 months and I just got my Pi 3B+ but instead of making a new card with the RP3 img I tried to use my pi zero retropie card and it works. I wasn't sure it would be compatible but it works.

My question is does using the zero img on a pi 3 have any limitations or reduction in performance?

Will my pi zero card use the full power of the Pi 3B's CPU or is it limited?

Basically what I'm asking is is there any advantage to me creating a whole new card using the pi 3 img instead of just using my zero card which is already done.

Thanks

dankcushions

(from memory...)

Yes, the default emulators for the 0/1 are often those that have higher performance, lower compatibility/accuracy. the pi 2/3 can run the emulators that have lower performance, higher compatibility/accuracy (but have the performance headroom that they can still run them full speed).

another issue is compiler flags. the 0/1 have a different generation of ARM cpu, without some of the features of the 2/3, so they have binaries compiled without these features that would presumably run less efficiently on a 2/3 than with the right flags.

finally, there are some emulator default settings set by default for 0/1 that are not optimal for the better performance of the pi 2/3. for example, the framebuffer resolution of retroarch is at 640x480 rather than full 1080p.

there may be some more things.

Efriim

Seeing as it is working then it must use the 3b+ firmware/overlay. Are the wifi and bluetooth interfaces up?
ifconfig

and check what the cpu says
lscpu

hhromic

@dankcushions said in Any Difference in performance using 0/1 img on Pi 3B+:

another issue is compiler flags. the 0/1 have a different generation of ARM cpu, without some of the features of the 2/3, so they have binaries compiled without these features that would presumably run less efficiently on a 2/3 than with the right flags.

That is perhaps the strongest argument to use the correct image for your device. For example, the Raspberry Pi 0/1 does not support NEON instructions, which are used by many emulators for speed. The Raspberry Pi 2/3 does have NEON and also have a different processor with faster instructions. All of that can only be taken advantage of if the binaries are compiled for them. Running a RPI0/1 image on an RPI2/3 basically does not take advantage of any of these optimisations and will just underuse the better aspects of these devices.