If one process is using only 4 bytes out of every 64 byte cache line fill, the rest of the line is wasted regardless of whether there are hundreds of other proc

If one process is using only 4 bytes out of every 64 byte cache line fill, the rest of the line is wasted regardless of whether there are hundreds of other processes loading different lines into the various levels of cache. It’s not using more of the cache, just using the same lines (or fewer) more effectively.