There is actually study which notes both Anrdoid and Linux Kernel. On Linux kernel the performance impact was from 2% to up to 25% and size increased around 30

There is actually study which notes both Anrdoid and Linux Kernel. On Linux kernel the performance impact was from 2% to up to 25% and size increased around 30%. On Android there was too much variance, but they note that Google got around 2-3% overhead, which sounds reasonable. Without hardware acceleration (e.g. Intel CET), it will likely come with great cost. But we are yet to see those benchmarks. But I would argue that you can take bigger impact for performance on Android or consumer phones anyway, since they are not performing high computation 24/7 usually, and they already have more computation power than most users require. https://www.duo.uio.no/bitstream/handle/10852/79829/master.pdf?sequence=8&isAllowed=y https://www.duo.uio.no/bitstream/handle/10852/79829/master.p...