FreeBSD/PC-BSD 10.2 vs. Ubuntu 15.04/15.10 Benchmarks
First up with the SQLite benchmark, PC-BSD 10.2 was faster than both Ubuntu 15.04 and 15.10. Between Clang and GCC, there was no performance difference. PC-BSD 10.2 uses the ZFS file-system by default while Ubuntu Linux continues running with EXT4.
While the SQLite test looked like ZFS on FreeBSD may be beating out Ubuntu with EXT4, in the Compile Bench test the numbers favored Ubuntu Linux.
For the PostMark mail server benchmark, it too favored the out-of-the-box Ubuntu 15.04/15.10.