Parallelization differences across machines

First off, with the new benchmarking library, you can benchmark on chocura.

I have noticed big differences between the parallelization speedups of silver, chocura, and tyner. For a small 4-thread test program, silver gets about a 2.9x speedup over sequential code (executed on silver). Tyner gets a 1.8x speedup over sequential code (executed on tyner). Chocura gets a 3.7x speedup for the same code over sequential execution on chocura.

Based on my experiences over the last couple of days, I'm going to use chocura for the derby. It seems to be the most stable.