Comment by lionkor

Hi, this might not be obvious to you so I wanted to explain it:

Testing on a single device, or two devices, is not enough. I'm on a laptop with 96 GB ram and a Ryzen AI 9 HX PRO 370, and it's running at 3 FPS.

The crucial part is browser performance and network latency. You need to test across multiple browsers, but also evaluate frame times, CPU load, GPU load, etc. so you can make a reasonable estimate whether it's fast or not.

Then, when you realize that its not good enough, e.g. on firefox, you use firefox's profiler to see which parts are slow. LLMs would guess, probably, but you have to measure.

Welcome to software engineering.