How to let 2 split screen apps run at top performance?

I noticed that on my Xiaomi 11i with the Snapdragon 888 processor, it is supposed to be one of the current top Android phones, with 8 cores and that only the Apple A14 Bionic has slightly higher performance than it. However, if I run two Pokemon Go using its Dual App split screen, then I noticed, if we look inside a gym, and a Pokemon (Venonat or Exeggutor) is swinging left and right, then every few seconds, on the top or bottom screen, the Pokemon would have a slight 0.2 second pause, so both apps are choppy every few seconds. If I use the app Activity Monitor, right after I boot up the phone so that no other app is running, I did see that every 6 to 10 seconds, all the cores of the processors would ramped up to 100%, so it looks like it is doing some work in the background. I noticed if I run one single instance of Pokemon Go, then it is smoother. But my question is, how can 8 cores not able to handle some slowing animating graphics. If anything, the swinging left and right repeatedly can even be "set it and forget it" -- everything done by the GPU (Adreno 660). So trying to solve it, I tried to tap the Version number of the system for a few times and went to Developer's Options, and from there, I set the background app to be: Running only 1 process at a time. So that should mean I have 7 cores running now for the 2 apps on screen? But after rebooting the phone and trying again, the same issue was still there. Is there a way to make it able to take 2 cores (or 3 cores) for each app, or just make them run at top performance and let any background process run with the remaining 2 cores? Or another way is, if there is a way to set the background processes only use up to 50% of the cores, so the main apps can always have 8 cores to use. **Update:** an insight to finding a solution: I noticed if we tap on a Pokemon and try to catch it, the Pokemon, if it is a flying Pokemon with their wings constantly flapping in the dual app, has really smooth animation and there is no tiny pauses ever. It may appear that when we look inside of a gym, usually six Pokemon are shown inside, so if both apps are looking inside of a gym, there can be 12 Pokemon moving inside. Even if 10 Pokemon have tiny movements only and two Pokemon have more apparent movements, it seemed it was possible that 12 threads were used, and so if there are 12 threads and 8 cores, maybe that's the reason that there can be tiny pauses. I am not sure if we can change the Settings on the phone to solve this, as these movements are very lightweight.