Using Workstations as Building Blocks for Parallel Computing

The key to eecient parallel computing on workstations clusters is a communication subsystem that removes the operating system from the communication path and eliminates all unnecessary protocol overhead. At the same time, protection and a stable multiuser , multiprogrammed environment cannot be sacriiced. We have developed a communication subsystem, called ParaStation2, which fulllls these requirements. Its one-way latency is 14:5s to 18s (depending on the hardware platform) and throughput is 65 to 90 MByte/s, which compares well with other approaches. We were able to achieve an application performance of 5.3 GFLOP running a matrix multiplication on 8 DEC Alpha machines (21164A, 500 MHz). ParaStation2 ooers standard programming interfaces, including PVM, MPI, Unix sockets , Java sockets, and Java RMI. These interfaces allow parallel applications to be ported to ParaStation2 with minimal eeort. The system is implemented on a variety of platforms, including DEC Alpha workstations running Digital Unix, and Intel PCs and DEC Alpha's running Linux.