The Tofu Interconnect

The Tofu interconnect was developed by Fujitsu as a national project of MEXT. The goal of the project is to develop one of the world's most powerful general purpose supercomputer systems and grand challenge applications, and to build a core research hub for computational science. The Tofu interconnect provides the scalability to implement the 10 petaFLOPS 'K computer' system which has more than 80,000 nodes. The network topology is a 6D mesh/torus. Quad network interfaces provide high throughput. The barrier interface is dedicated to offloading collective communications. This paper describes the Tofu interconnect architecture, the Tofu network router, the Tofu network interface, and the Tofu barrier interface, and also presents preliminary evaluation results.