Benchmarks show Linux beats OSX on a MacMini:

All of the benchmarks under both OS X and Linux were facilitated using the open-source Phoronix Test Suite benchmarking software. All of the hardware was the same throughout testing: the reported differences on the automated table above just come down to differences in what the OS reports, such as the difference between the CPU base frequency and turbo frequency, etc. On the following pages are the initial results with more interesting data points to come shortly.

Read More: http://www.phoronix.com/scan.php?page=article&item=osx-fedora21-vivid&num=1