Which cache eviction policy?

Policies for deciding which key to drop when a cache is full. A cache holds at most `capacity` keys, so when a new one arrives something has to go, and which one is the whole question. The difference between a good and a bad eviction rule on the same workload is routinely ten points of hit rate, for identical memory and near-identical cost per operation.

Pick up to four and run them on the same trace. Any difference you see is the policies. The URL holds the whole setup, so you can share a comparison as a link.

The runner uses the same code as the benchmark tables on the page. It replays a shorter prefix of each trace, so use the tables for the final numbers.