Heres a test of the same machine in both OS's. Windows makes a huge difference in FPS on the same hardware.
Model: Mac Pro Late 2013
Graphic card: 2x AMD FirePro D700 6144 MB (total 12288mb)
Harddisk: Apple Flash storage 1Tb
Processor: 3,0 GHz 8-Core Intel Xeon E5
Memory: 32 GB 1867 MHz DDR3 ECC
Resolume 4.1.8
Output Setup: 1 Control monitor at 2560x1440, 1 Fullscreen output at 1920x1200
OS: Windows 8.1 Test with both CrossFire mode enabled (and forced) and disabled.
Benchmark for 1920x1080
Clean content: 22 layers
Noise content: 20 layers
OS: OS-X 10.9.2
Benchmark for 1920x1080
Clean content: 16 layers
Noise content: 10 layers