A Tale of Two Technology Disruptions

With power dissipation severely limiting the frequency scaling of microprocessors, the emergence of chip multiprocessors (CMPs) had shifted computingto embrace highly parallel multicore architectures. Realizing performance in these newgenerations of chips is becoming increasingly dependent on how efficiently applications can exploit the growing number of parallel resources. Whereas computation power as measured in FLOPs was the key metric of past microprocessors, performance in today?s CMPs is dominated by data movement challenges. In this so-called ``communications bound?? era of computing, new technologies are sought that can deliver energy-efficient high-bandwidth interconnectivity. While optics is a natural communications technology with broad success in long-haul fiber optic telecommunications, integration at the chip scale, particularly with silicon, had been challenging.