Many-Core vs. Many-Thread Machines: Stay Away From the Valley

The authors study the tradeoffs between Many-Core machines like Intel's Larrabee and Many-Thread machines like Nvidia and AMD GPGPUs. They define a unified model describing a superposition of the two architectures, and use it to identify operation zones for which each machine is more suitable. Moreover, they identify an intermediate zone in which both machines deliver inferior performance. They study the shape of this "Performance valley" and provide insights on how it can be avoided.