Ubuntu 11.10 vs. Mac OS X 10.7.2 Performance
The DES performance in John The Ripper was similar between Apple's Mac OS X and Canonical's Ubuntu Linux.
For the MD5 and Blowfish tests, the GCC 4.2.1-built version did not perform well at all. The LLVM/Clang 3.0-built binary came in a short ways behind Ubuntu 11.10.
Mac OS X 10.7.2 with Xcode4 was also a ways behind Ubuntu 11.10.