The Xeon Phi cores trail the latest Intel processors in architecture but they do incorporate features like a 512-bit wide vector engine (Fig. 3) . The Knights Corner core has a 32 Kbyte L1 instruction and data cache and a 512 Kbyte L2 cache. The cores do support 4 threads but they do not employ the same type of "hyperthreading" found in Intel's Core processors. The Xeon Phi's multithreading is more amenable to HPC applications where each thread has enough resources so it will not be blocked. Hyperthreading is designed to optimize hardware utilization. Multithread is designed to optimize thread performance. Many HPC applications disable hyperthreading. Virtualization is also a feature not found in the cores because the initial target is HPC versus virtualized cloud services.