When user does not specify `-Xms`, JVM ergonomics guesses the initial heap size, based on `InitialRAMPercentage` setting, currently set at 1/64 of physical RAM. The initial heap size drives the startup times, because GCs need to initialize their internal data structures, e.g. remsets, card tables, or even heap memory itself for the initial heap. This heuristics had not changed for decades, and modern computers ship with much larger system memories, which initializes a very large initial heap.

This release trims `InitialRAMPercentage` to `0.2`, improving the startup time for default JVM modes. In case this change causes any problems, users are advised to either specify more reasonable `Xms` explicitly, or override the `InitialRAMPercentage` setting.