Bare-Metal Execution of Hard Real-Time Tasks Within a General-Purpose Operating System

Integrating high performance and real-time demands on multi-processor systems is a challenging task. We present our concept of isolating processes from a general-purpose operating system without deeply invading modifications. This allows executing code on dedicated CPUs with minimum latency and jitter like bare-metal on micro-controllers. The unbounded execution of mixed critical processes on the same system induces performance interference in real-time tasks. We present the implementation of isolated partitions on multi-processor x86 systems running Linux and describe challenges restoring operating system stability. This work also presents our experience with Non-Uniform Memory Access architectures that allow to partition the system in a way that the impact to memory and I/O transfers of other partitions is minimized. 1998 ACM Subject Classification D.4.7 Real-time systems and embedded systems