ATAC: A Manycore Processor with On-Chip Optical Networkhttp://groups.csail.mit.edu/carbon/?page_id=62

ATAC is a new 1000-core multicore computing system that leverages recent advances in nanophotonics to communicate values between cores. The cores within the ATAC chip can communicate almost instantaneously given the low latency and high bandwidth properties of optical communications. This global communication infrastructure will improve performance, energy efficiency and programmability of large scale multicores.

ATAC’s optical network is configured such that all cores are effectively connected via an optical waveguide. Every core is able to broadcast to every other core while simultaneously receiving from every other core. ATAC’s efficient all-to-all communication ability allows parallel algorithms to scale to large numbers of cores, partly enabled by wavelength division multiplexing. Given this low communication cost, writing ATAC programs that achieve high performance is usually more straightforward than on conventional multicore architectures. ATAC’s communication substrate also enables extremely efficient shared memory protocols that scale to much larger numbers of cores than traditional shared memory implementations. Our goal with ATAC is to explore the relatively new area of integrating optics into large-scale multicores, focusing on architecture, programming, and energy efficiency.