Serious lag on Reicast/DeSmuME 2015


First off, I’d just like to say I’m new to this forums, and new to “properly” setting up RetroArch; I’ve been using it on and off for the past few years for GameBoy games, but I’m moving on to larger games because I have more storage on my SD card (used to do gameplay videos that I’d record there, but I record on PC now). Anyways, I’d just like to say thank you for making this, the amount of emulators/devices supported is insane.

So, I’ve been having some serious (and unexpected) issues with both the Reicast and DeSmuME cores. Reicast runs smoothly loading the Dreamcast cores and most loading screens, but whenever the actual game characters come into play, the emulator goes from 60fps to, like, 10. It’s not just laggy either, it physically slows the emulator. I’ve been able to fix the lag with a few performance tweaks and using the threaded rendering option, but threaded rendering then results in serious input lag, with a 5-10 second delay between me pressing a button and it registering. This applies to both game controls and the RetroArch menu button. Turning off threaded rendering fixes this, but then my game speed goes from full to roughly 1/3 to 1/4 speed. Now, I’ve used the actual Reicast emulator, and it ran perfectly fine, no slowdown. The games I’m using are Jet Grind Radio and Sonic Adventure.

It’s similar on DeSmuMe 2015, the menu screens are all smooth but the moment I enter the game it begins to lag. I’ve used DeSmuMe (as well as other DS emulators, such as DraStic) and they all run smoothly, no lag at all. There’s no threaded rendering option to try, as far as I can see. The games I’m running are Pokemon Platinum and Pokemon Soul Silver.

I would try to use the fast forward option, but I can’t seem to find it on any menu.

Running Android 7.0 Nougat, if that matters. Any help would be appreciated, other emulators run perfectly fine (game boy/color/advance, ps1, n64, genesis, nes)


Desmume is frequently slow on Android on all but the most powerful devices. Drastic isn’t really a direct comparison, as it is 100% designed around being full speed on low-power Android devices.

For Reicast, the libretro core is significantly different from standalone at this point. The order-independent transparency (OIT) setting is the biggest difference in both accuracy and performance, so if you need to speed it up, that’s the first place to look.


If using Threaded Rendering (and you should use it if you want good performance), you need to set Poll Type Behavior to ‘Early’ in the RA settings. This will fix the input lag.

Also, if using the 32-bit version , try disabling the DSP to improve performance.


Appreciate the replies, I’ll try out what you suggested for Reicast and hopefully get it working. As for DesMuME, I’ll just have to try MelonDS or a different emu. Thanks!