This paper presents the design and implementation of a new I/O networking infrastructure, named PaScal (parallel and scalable I/O networking framework). PaScal is used to support high data bandwidth IP based global storage systems for large scale Linux clusters. PaScal has several unique properties. It employs (1) Multi-level switch-fabric interconnection network by combining high speed interconnects for computing inter-process communication (IPC) requirements and low-cost Gigabit Ethernet interconnect for global IP based storage/file access, (2) A bandwidth on demand scaling I/O networking architecture, (3) open-standard IP networks (routing and switching), (4) multipath routing for load balancing and failover, (5) open shortest path first (OSPF) routing software, and (6) Supporting a global file system in multi-cluster and multi-platform environments. We describe both the hardware and software components of our proposed PaScal. We have implemented the PaScal I/O infrastructure on several large-size Linux clusters at LANL. We have conducted a sequence of parallel MPI-IO assessment benchmarks on LANL's Pink 1024 node Linux cluster and the Panasas global parallel file system. Performance results from our parallel MPI-IO benchmarks on the Pink cluster demonstrate that the PaScal I/O Infrastructure is robust and capable of scaling in bandwidth on large-size Linux clusters

During the last few years, software product line engineering has gained significant interest as a way for creating software products faster and cheaper. But what architecture is needed to integrate huge amounts of products, from different product lines? This paper describes such an architecture and its support processes and tools. Through cases, it is illustrated how the architecture is used to integrate new --- and old --- products in such diverse integration projects as vessel motion control, airport baggage handling systems, pulp&paper and oil&gas, in a very large organization. However, in a large organization it is a challenge to make everyone follow an architecture. Steps taken to ensure global architectural consistency are presented. It is concluded that a single architecture can be used to unify development in a huge organization, where the distributed development practices otherwise may prohibit integration of various products.