TransactionalMap vs SynchronizedMap

Question

When should one prefer Akka TransactionalMap over regular immutable map mixed in with SynchronizedMap and vice versa? (Or am I comparing apples to oranges here?)

Answer 1

Use the transactional map when you want to have transactions. Use Ctries/ConcurrentHashMap/NonblockingHashMap for mixed read-writes and CAS+immutable.Map for very-very-infrequent writes.