Is it there any LRU implementation of IDictionary?

Question

I would like to implement a simple in-memory LRU cache system and I was thinking about a solution based on an IDictionary implementation which could handle an hashed LRU mec

Answer 1

I like Lawrence's implementation. Hashtable + LinkedList is a good solution.

Regarding threading, I would not lock this with[MethodImpl(MethodImplOptions.Synchronized)], but rather use ReaderWriterLockSlim or spin lock (since contention usually fast) instead.

In the Get function I would check if it's already the 1st item first, rather than always removing and adding. This gives you the possibility to keep that within a reader lock that is not blocking other readers.