High level description and implementation of resource schedulers

Resource sharing problems can be described in three basically independent components. • The constraints the resource places upon sharing because of physical limitations and consistency requirements. • The desired ordering of resource requests to achieve efficiency—either efficiency of resource utilization or efficiency for processes making the requests. • Modifications to the ordering, to prevent starvation of processes waiting for requests which might otherwise never receive service. A high level description language to specify these components of resource sharing problems is introduced. An implementation that lends itself to mechanical synthesis is described. Synthesis of the scheduler code by-passes the long and error- prone process of someone doing the coding themselves. Proof techniques at the high level description level are introduced to show how to prove schedulers, synthesized from their description, are or are not deadlock and starvation free. Solutions to the classical resource sharing problems of producer/consumer, reader/ writer, and disk scheduler (to the sector level) are shown to illustrate the expressiveness of this description language.