Into concurrent LRU caching once again

But this time, with a more product oriented point of view, instead of researching.

http://openmymind.net/High-Concurrency-LRU-Caching/

http://www.ebaytechblog.com/2011/08/30/high-throughput-thread-safe-lru-caching/

http://www.cs.cmu.edu/~dga/papers/memc3-nsdi2013.pdf