The Cenju Project was initiated at the Univeristy of Houston in November 1994 to investigate the operating system requirements of parallel applications. Working closely with NEC C&C Research Laboratories, we have ported a 4.3BSD UNIX server and applications to the Cenju-3. The UNIX servers allow the Cenju-3 to be treated as a network of workstations.

System software we have developed includes customizable virtual memory, a parallel shell, a distributed shared memory system, a MPI-IO library, and a MPI profiling environment. Customizable virtual memory hides the details of reading and writing to disk while allowing the application writer to control swapping policies. The parallel shell allows users to control parallel applications with C shell-like scripts. The distributed shared memory system utilizes user-defined memory access patterns to manage memory access requests and efficiently maintain memory consistency. The philosophy of the system is unique because it focuses more on performance at the cost of sacrificing transparency. The MPI-IO library provides a flexible parallel I/O interface. The MPI profiling environment allows application writers to study the communication behavior of MPI applications.