Developing Applications for Multicomputer Systems on Workstation Clusters

Much computational power on state-of-the-art multicomput-ers like the Paragon is wasted with porting applications. Using networks of workstations is an attempt to withdraw this workload from multicom-puter systems. Therefore an environment is needed which provides the programming interface of multicomputers on coupled workstations. The paper describes the design and implementation of the NXLib environment which allows to use Ethernet coupled workstations as a development platform for applications targeted for Intel Paragon systems. A drawback of multicomputers is that porting existing applications onto those systems often requires enormous eeorts. Applications have to be parallelized which leads to frequent test runs during the implementation. Therefore, much workload on multicomputer systems consists of test and debugging runs. To withdraw some of this load, an environment is needed which allows the implementation of applications for multicomputer systems on diierent hardware platforms. Today, typical environments in universities and companies consist of several networked workstations. The basic architecture of multicomputer systems and coupled workstations is similar: independent processing elements (nodes or workstations) which are interconnected. In diierence to the multicomputers' high performance interconnection network, workstations currently use a slower interconnect. In addition the network has to be shared with other machines and users which are also connected to the network. State-of-the-art multicomputers like the Paragon ooer a proprietary message passing environment. An implementation of that library on coupled workstations would allow for using interconnected workstations as a development platform for applications where the production code should nally run on a multicomputer ? This project was partially funded by a research grant from the Intel Foundation.