Showing posts from January, 2013

Caliper - Java Micro-Benchmark Helper

Lots of us faced with some performance challenge encountered the problem with the right measuring time of some method invocation, loop iteration, etc. The first solution that comes to mind is to use System.nanoTime() before and after execution. And after subtraction we will get our result. But are we sure that the simplest answer is also the best one? What about comparing multiple measurements? What about JIT impact? Fortunately, a new king is in town - the Caliper. It solves all these problems and protects us from committing other standard errors. It’s not my idea to write another tutorial (those available in Caliper’s source repository are good enough to start using this framework). Instead, let's go into details of how to interpret obtained results and choose the right parameters to perform benchmark. The first important thing that Caliper does is it creates full scenarios cartesian using: defined virtual machines benchmark methods (for time measurements it should be pu