Runtime commited heap resizing
New day, new version of Java... nice :) We used to update minor Java versions mostly due to security issues. But sometimes those minor updates brings us brand new, awesome features. So was for example with 7u40 which brought us awesome Mission Control known from JRockit. (If you are interested in tracking changes across Java updates take a look at http://www.oracle.com/technetwork/java/javase/8all-relnotes-2226344.html for Java 8 or http://www.java.com/en/download/faq/release_changes.xml for Java 7) Same situation is now with versions 7u60 and 8u20 . Since now flags MinHeapFreeRatio and MaxHeapFreeRatio became manageable, which means we can change its values... in runtime :)