Cliff Click’s 2008 JavaOne talk about the NonBlockingHashTable
I’m a bit late to this data structure — highly scalable, nearly lock-free, benchmarks very well (except with the G1 GC): http://edwwang.com/blog/2012/02/10/concurrent-hashmap-benchmark/ . Having said that, it doesn’t cope well with frequently-changing unique keys: http://sourceforge.net/tracker/?func=detail&aid=3563980&group_id=194172&atid=948362 . More background at: http://www.azulsystems.com/blog/cliff/2007-03-26-non-blocking-hashtable and http://www.azulsystems.com/blog/cliff/2007-04-01-non-blocking-hashtable-part-2 This was used in Cassandra for a while, although I think the above bug may have caused its removal?
(tags: nonblockinghashtable data-structures hashmap concurrency scaling java jvm)