Guys, I have finally reviewed and accepted contribution made by Ilya Lantukh. That was pretty useful change - it removes data duplication (after years of having one!), i.e. earlier we had to store cache entry by reference in 2 maps, now only in 1. It brings up to 20% for memory efficiency (this depends on size of keys and values).
Thanks to Ilya and other reviewers - Sam and Alex Goncharuk! Here is link to ticket - https://issues.apache.org/jira/browse/IGNITE-2948 --Yakov
