Building blocks for an exa-scale operating system

Abstract

Currently, high performance systems are mostly used by splitting them into fixed-size partitions which are completely owned and operated by applications. Hardware architecture designs strive to remove the operating system from the critical path, for example using techniques such as RDMA and busy waiting for synchronisation. Operating system functionality is restricted to batch schedulers that load and start applications and to I/O. Applications take over traditional operating system functionality such as balancing load over resources. In exa-scale computing, new challenges and opportunities may put an end to that mode of operation. These developments include applications too complex and too dynamic to do application-level balancing and hardware too diverse to maintain an application-level view of a fixed number of reliable and predictable resources. The talk will discuss examples of operating system building blocks at various system levels that may receive new appreciation in exa-scale supercomputing. These building blocks include schedulers, microkernels, library OSes, virtualization, execution time predictors and gossip algorithms that need to be combined into a coherent architecture.