Program Execution Control in a Multi CMP Module System with a Look-Ahead Configured Global Network

The paper presents a method for the optimized control of program execution in modular systems based on Chip Multi Processor (CMP) modules interconnected by a special global inter-connection network. The applied CMP modules are based on communication on the fly, which is a novel efficient group communication paradigm implemented inside the interconnection network. Communication on the fly is based on a synergy of dynamic processor switching between memory modules and data read on the fly mechanism, which enables to many processors simultaneous reads of data, when present on shared memory buses. The paper presents a two-stage scheduling algorithm for programs expressed in a graph notation. The first stage schedules program tasks inside the CMP modules using an algorithm based on the notion of moldable tasks. In the result, a scheduled program moldable task graph is produced. The moldable task graph is next structurized for optimized communication execution in the global network working according to the look-ahead link connection setting paradigm. Results of simulation experiments evaluate the efficiency and other properties of the proposed architectural solution.