Ok, I tried disabling the UART in the .fex (and it did end up disabled once I rebooted) but this didn't change anthing else as far as I could tell....
Edit:
running cpuburn-a7 ... I only have 1 core enabled and everything I am not using disabled in the .fex file. (this is an automatic AVR 32u4 board flasher so I don't need much ummph) Also the ram is running at 132Mhz.
Stop monitoring using [ctrl]-[c]
Time CPU load %cpu %sys %usr %nice %io %irq CPU
22:07:21: 240MHz 0.44 12% 8% 0% 2% 0% 0% 39°C
22:07:27: 240MHz 0.49 76% 11% 61% 1% 0% 0% 40°C
22:07:33: 240MHz 0.53 100% 3% 95% 0% 0% 0% 40°C
22:07:39: 240MHz 0.56 100% 3% 95% 0% 0% 0% 40°C
22:07:45: 240MHz 0.60 100% 3% 95% 0% 0% 0% 40°C
22:07:50: 240MHz 0.71 100% 7% 90% 1% 0% 0% 40°C
22:07:56: 240MHz 0.83 100% 2% 97% 0% 0% 0% 40°C
22:08:01: 240MHz 0.84 100% 5% 91% 2% 0% 0% 40°C
22:08:07: 240MHz 0.94 100% 5% 91% 2% 0% 0% 40°C