Module swim.util
Package swim.util

Class HashGenSet<V>


  • public class HashGenSet<V>
    extends Object
    A hashed generational set evicts the least recently used value with the worst hit rate per hash bucket. HashGenSet is a concurrent and lock-free LRFU cache, with O(1) access time, that strongly references its values.

    Maintaining four "generations" of cached values per hash bucket, the cache discards from the younger generations based on least recent usage, and promotes younger generations to older generations based on most frequent usage. Cache misses count as negative usage of the older generations, biasing the cache against least recently used values with poor hit rates.

    The evict(V) method is guaranteed to be called when a value is displaced from the cache.

    • Constructor Detail

      • HashGenSet

        public HashGenSet​(int size)
    • Method Detail

      • evict

        protected void evict​(V value)
      • put

        public V put​(V value)
      • remove

        public boolean remove​(V value)
      • clear

        public void clear()
      • hitRatio

        public double hitRatio()