Java 7 vs. Java 8: Performance Benchmarking of Fork/Join

with the recent release of java 8, developers are still just beginning to asses the strengths and weaknesses of the new platform. the most pressing question is: does java 8 have the fastest jvm so far? a good way to asses the progress of java 8 is to test its ability to work with something that was new to java 7... fork/join.

oleg shelajev uses the "infamous" java microbenchmark harness project (jmh) to create a benchmark test for the two most recent versions of java. but before implementing the benchmark, he takes the time to give a brief overview of fork/join and how it changes between java 7 and 8.

here is a graph of the results :

based on these results, oleg recommends taking a chance and upgrading to java 8, especially if you are working with mapreducing or fork/join. this is his interpretation of the data that lead him to that conclusion:

one can see that the baseline results, which show the throughput of running the math directly in a single thread do not differ between the jdk 7 and 8. however, when we include the overhead of managing recursive tasks and going through a forkjoin execution then java 8 is much faster. the numbers for this simple benchmark suggest that the overhead of managing forkjoin tasks is around 35% more performant in the latest release.

check out the full article ! it is very informative, has great visuals, and tackles complexity with clarity.