Deterministic Communication Server Model And Instance: Net SPU

In many safety related system, network is a crucial requirement. Especially in the High Available system, the safety related performance is as important as communication quality. Much of the motivation for multi-core architectures of the first generation have to do with providing a deterministic and reliable computation resource for services that would be hard to guarantee with a general purpose CPU only - at least not with an acceptable impact on available throughput. The utilization of CELL in this respect just caters for the requirements - the computational resources are isolated in separate hardware which can provide well guaranteed performance and the design of co-processors is general problem specified and simplified for allowing better prediction of performance, especially that the high-loads on the general purpose CPU (PPU) would not affect critical services on the co-processors (SPU). In this paper, we describe a framework using SPU as a server model for deterministic communication based on contracts. The network server implements the low level device handling and protection and monitors the device performance, dynamically readjusting parameters to compensate developments, triggering reactions, and notifying applications on contract violations if necessary. Because the basic model is transparent towards the user and the device, it can be widely used in many areas.