We consider the problem of implementing shared objects in uniprocessor and multiprocessor real-time systems in which tasks are executed using a scheduling quantum. In most quantum-based systems, the size of the quantum is quite large in comparison to the length of an object call. As a result, most object calls can be expected to execute without preemption. A good object-sharing scheme should optimize for this expected case, while achieving low overhead when preemptions do occur. In this paper, we present several new shared-object algorithms for uniprocessors and multiprocessors that were designed based upon this principle. We also present scheduling analysis results that can be used in conjunction with these algorithms.
['James H. Anderson', 'Rohit Jain', 'Kevin Jeffay']
Efficient object sharing in quantum-based real-time systems