Lastest Mupen64Plus core performace hit

Libretro Cores
#1

I have two different cores for Mupen64Plus since I’ve not completely switched over from Retro Arch 1.5.0 and have found that the lasted core brings a massive performance hit for my little Sandy Bridge i3 when I loaded up Mupen in 1.6.9. I get massive amounts of lag and crackling audio whenever I use the latest core which is 2.5 6f80cbc. I initially thought that it was the new Retro Arch build until I saw that I had two different versions of the Mupen core between the two Retro Arch releases. When I go back to the one I downloaded on May 29th which is version 2.5 407bcd4 and turn off hard GPU sync almost every game that doesn’t have emulation issues runs with no problem. I looked at my on screen statistics while running both versions of the Mupen64Plus core and found that my idle cpu usage was running around 5% and normally goes no higher than 18%. when using the older version. On the newer version my idle cpu usage is normally around 12% and presses to over 25% alot which is where I start getting lag and crackling audio. Now since I have an i3 25% normally means that one of the threads to one of my CPU cores is capped out or really close to. So I observed the target framerate of each core version. The older version targets the original framerate of the game where as the new core simply targets 60 frames which is where I believe I’m getting the performance hit because most of the time it can’t hit that target. The older version’s framerate continuously varies. I know on the ParaLLel64 emulator there is an option to target the original framerate or a full 60. I don’t see an option for that on the Mupen64Plus core. So I’m currently sticking to the old version like glue until I can figure out what’s going on with the latest core because I won’t be able to play jack if I move to the new one. Any ideas?

My PC is again,

Core i3 2120 GTX 650 4GB RAM Windows 7 X64

#2

Actually upon further investigation the problem seems to be tied to Vsync. Whenever I turn it off I have screen tearing but no lag or stutter. If I turn v-sync on I get poor performance. Changing the number of GPU sync frames or turning threaded video does not help.

#3

Ok so don’t everyone jump in at once! Lol

Well for what it’s worth I ended up finding a fix. I invoked v-sync and triple buffering through the Nvidia control panel and set threaded optimization from off to auto.

1 Like
#4

Ya looks like you were frequently dropping below 60 fps with vsync causing it to go down to 30 fps syncs. The downside to using triple buffering to increase smoothness is slightly increased input lag since the frames will be slightly older but it’s worth it if vsync is choppy without it.

#5

Yeah you would think that except that when vsync wasn’t engaged at all the frame rate never dropped and doesn’t drop anymore now with vsync engaged via the driver. It might just be one of those quirks that have more to do with the hardware that’s being used and not so much about its capability. I would think that a Core i3 2120 is more than capable of running Mupen64Plus. Plus I’ve noticed that my CPU usage actually increased since I used the driver’s vsync vs Retro Arch.

#6

One other thing that gave me better performance in RetroArch was changing “power management mode” to max performance in nvidias control panel. I still wanted the default to be optimal power so I added retroarch manually to its program settings.

Oh also, what did you have set as your audio latency when you were getting the chopiness earlier? For N64 i kept it at 64 since any lower and I had issues in some games.

#7

My audio latency is at the default 64.