High Performance Systems and Interconnects

Recent advances in interconnection technologies have made clustered systems built out of commodity components an attractive option for providing scalable computational and storage infrastructure in a cost-effective manner. Such systems comprise numerous hardware (processors, memory, peripheral buses, interconnect NICs, storage controllers and media) and software (embedded firmware, OS kernel, NIC and block device drivers, file systems, communication middleware, application libraries and software) components. Understanding the intricate interactions between them and streamlining their semantics is key to achieving good performance.

Our research studies the effects of shared architectural resources on SMP clusters and focuses on I/O and scheduling techniques to better adapt the execution of compute and I/O-intensive applications to the underlying architecture.

MemBUS

MemBUS concerns the design and implementation of memory and network bandwidth aware scheduling policies, in order to reduce the impact of memory and network contention and improve system throughput for multiprogrammed workloads on cluster of SMPs.

gmblock

gmblock is an ongoing effort to implement efficient block-level storage sharing over modern processor- and DMA-enabled interconnects such as Myrinet. Its design focuses on the flow of data in a network block device system, aiming to improve the efficiency of remote block I/O operations by completely removing the CPU and main memory from the critical path. Data are pipelined directly from the storage medium to the interconnect NIC and link, thus reducing the impact of network I/O on the locally executing processes.

Publications

• E. Koukis, A. Nanos and N. Koziris, “Synchronized Send Operations for Efficient Streaming Block I/O over Myrinet,” Proceedings of the Workshop on Communication Architecture for Clusters (CAC 2008), held in conjunction with the 22nd International Parallel and Distributed Processing Symposium (IPDPS 2008), Miami, FL, USA, 14-18 April, 2008, to appear
• E. Koukis and N. Koziris, “Efficient Block Device Sharing over Myrinet with Memory Bypass,” Proceedings of the 21th International Parallel and Distributed Processing Symposium (IPDPS 2007), p. 29, Long Beach, CA, USA, 26-30 March, 2007
• E. Koukis and N. Koziris, “Memory and Network Bandwidth Aware Scheduling of Multiprogrammed Workloads on Clusters of SMPs,” Proceedings of the 12th International Conference on Parallel and Distributed Systems (ICPADS 2006), pp. 345-354, Minneapolis, MN, USA, 12-15 July, 2006
• E. Koukis and N. Koziris, “Memory Bandwidth Aware Scheduling for SMP Cluster Nodes,” Proceedings of the 13th Euromicro Conference on Parallel, Distributed and Network-based Processing (PDP '05), pp. 187-196, Lugano, Switzerland, 6-11 Feb. 2005