Comment by loeg
5 days ago
Apple arm64 supposedly has 64-byte L1 cache line size and 128-byte L2? How does that work? Presumably the lines are independent in L1, but can different cores have exclusive access to adjacent lines? What's the point of narrower lines in L1?
Maybe the point isn't narrower lines in L1 but wider lines in L2? Implicitly bringing in more data to the L2 cache but allowing the CPU to pick smaller chunks of it into L1 cache to work on. Something like a forced prefetch or something? Honestly no idea.