ConcurrentTLru

ConcurrentTLru is a thread-safe bounded size pseudo TLRU. It's exactly like ConcurrentLru, but items have TTL. This page describes how to use the ConcurrentTLru.

Usage

ConcurrentTLru is intended to be a drop in replacement for ConcurrentDictionary, but with the benefit of bounded size based on a TLRU eviction policy.

This code sample illustrates how to create an LRU then get/remove/update items:

int capacity = 666;
TimeSpan ttl = TimeSpan.FromMinutes(5);
var lru = new ConcurrentTLru<int, SomeItem>(capacity, ttl);

// Get
bool success1 = lru.TryGet(1, out var value);
var value1 = lru.GetOrAdd(1, (k) => new SomeItem(k));
var value2 = await lru.GetOrAddAsync(0, (k) => Task.FromResult(new SomeItem(k)));

// Remove
bool success2 = lru.TryRemove(1);

// Update
var item = new SomeItem(1);
bool success3 = lru.TryUpdate(1, item);
lru.AddOrUpdate(1, item);