Introduced by Maurice Herlihy, Nir Shavit and Moran Tzafrir in 2008,
hopscotch is a way of resolving hash collisions using open addressing
and is also useful in implementing a concurrent hash table.
"Cuckoo hashing is a scheme in computer programming for resolving hash collisions of values of hash functions in a table, with worst-case constant lookup time." - https://en.wikipedia.org/wiki/Cuckoo_hashing
this is related to #318
Michael & Scott's paper on non-blocking concurrent queues. This paper contains a large amount of pseudocode. Published in Proceedings of the Fifth ACM Symposium on Principles and Practice of Parallel Programming.