Preloading Schemes for the PASM Parallel Memory System

Parallel processing systems, such as PASM, employ a large number of primary memory modules. A memory system organization using parallel secondary storage devices and double-buffered primary memories has been devised for PASM in order to prevent primary/secondary memory transfers from becoming a bottleneck. To efficiently use the memory system, it is desirable to overlap the operation of the parallel secondary storage devices with computations being performed by the processors. Due to the dynamically reconfigurable architecture of PASM, the processors which will execute a new task will not be selected until they are ready to execute the task. That is, to make effective use of double-buffering, a task must be preloaded prior to the final selection of the processors on which it will execute. Two schemes which allow for the parallel secondary storage devices to preload input data and programs into the primary memories so that system performance can be improved are presented and compared. Results show that both methods are effective techniques.