Pointer tagging for x86 systems

But the Mill is legit crazy. I forget whether they track dirtiness on a per byte or per bit level, but that level of detail in tracking dirtiness can only hurt. If anything, we should track dirtiness at a super-cache-line level and move things around in a group of two or four cache lines. Of course, that comes with a false sharing problem, which is why it hasn't happened yet.

There's always trade-offs and people can have a real conversation about whether 32, 64 or 128 bytes is the correct size of a cache line, but there's a knee to this curve and 1-4 bytes is outside the scope of sane conversation.