Comment by joha4270

You can find more in the RISC-V privileged specification[1], section 3.7 I don't have any benchmarks and I think no such generalized benchmarks exists since its a specification and every core brings its own implementation (or none, its optional). With that said, its simple and probably effectively zero overhead, but its also much less capable than what a MMU can do. Its a "protect some firmware against the OS" or "absolute minimum hardware for some memory protection in a cheap MCU", not a competitor to full fat virtual memory.

[1]: https://docs.riscv.org/reference/isa/_attachments/riscv-priv...