The microbenchmark suite

Based on Java Microbenchmark Harness (JMH), this feature adds a basic suite of microbenchmarks to the JDK source code, with the following proposed directory structure:

jdk/jdk
    .../make/test
    .../test
       .../micro/org/openjdk/bench
           .../java
                .../vm

Since the microbenchmark suite will be located with the JDK source code, it will make it simpler for developers to locate and run existing microbenchmarks, and create new ones. As existing features are updated or removed from a JDK version, it will be simple to update a microbenchmark. Also, when developers run a microbenchmark they can use JMH's powerful filtering to run selected benchmarks.

Although the microbenchmark suite and its building will be integrated with JDK and its build system, it will have a separate target. Developers will need to specify additional parameters...