> Is that important, though? As soon as you start processing any meaningful amount of data, won't your OS be evicted from the cache anyway? Writable caches yes

> Is that important, though? As soon as you start processing any meaningful amount of data, won't your OS be evicted from the cache anyway? Writable caches yes. However many (most?) modern processors also contain a code-only cache which can be used for OS caching without any need to flush. The raspberry pi 4 can fit many modern microkernels in their tiny immutable cache, so it gains a massive caching benefit by being small. > Are there exceptions to this that you are aware of, and can elaborate on? You’re probably right, I was unaware of the extent of the kernel module usage. Regardless, the smallest common kernel in use that I know about is for alpine Linux and that is still at least 100MB, which is dramatically larger than the <1MB microkernels that are typically available.