Using the excellent [JMH microbenchmark framework](http://openjdk.java.net/projects/code-tools/jmh/) developed by the Oracle JVM performance team, extremely accurate microbenchmarks were created to isolate and measure the overhead of HikariCP and other popular pools. You can checkout the [HikariCP benchmark project for details](https://github.com/brettwooldridge/HikariCP-benchmark) and review/run the benchmarks yourself.