> Moreover there's also the instruction cache, and I'm not sure if you can disable caching for that in a meaningful way? Intels used to boot with their caches

> Moreover there's also the instruction cache, and I'm not sure if you can disable caching for that in a meaningful way? Intels used to boot with their caches disabled, but I haven't worked with them in forever, and never multicore. I worked with a lot of microcontrollers, and it's not uncommon to be able to disable the instruction cache there. There are a few things that require the data caches too, like atomic accesses on ARM. Usually we were doing something fairly short though in our realtime code, so it was easy enough to map just the memory it needed as uncacheable.