The current solution for flushing the “existing” cache is very simple, it simply checks every 1000 times it adds an element to the cache for invalidated elements in the cache and removes them. That means the elements not necessary get removed if there are not at least 1000 actions.

Instead we should have a “Harakiri“ Thread handling the cache, a “Harakiri“ Thread is a single thread that kills itself when no longer needed.

The new solution should also log (level=debug) what it is exactly doing so we can observe how the cache is growing/shrinking.