Abstract: A computer system comprises a plurality of processes, each having an associated memory region, and a shared memory region shared by the processes. One of the processes is configured to control allocation of space for an array in the shared memory region, generate a descriptor therefor pointing to the allocate space and transmit the descriptor to the other processes. Therafter, all of the processes are configured to identify regions of the array for which they are to process data therein, and to perform predetermined processing operations in connection therewith.

Abstract: A system for facilitating thread-safe message passing communications among threads in respective processes includes arrangements for coordinating collective communication operations, as between collective and non-collective communication operations, and as among threads in a process receiving messages contemporaneously. For collective communication operations, a master thread is provided and each process is provided with a slave thread. When a user thread in a process is to engage in a collective operation, it notifies its process's slave thread, which notifies the master process. When the master process has received notifications the slave threads of all of the processes which have user threads that are to engage in the collective operation, it notifies the slave threads that the collective operation is to proceed.