Allocation and scheduling of complex periodic tasks

Abstract

A static algorithm for allocating and scheduling components of complex periodic tasks across sites in distributed systems is discussed. Besides dealing with the periodicity constraints (which have been the sole concern of many previous algorithms), this algorithm handles precedence, communication, and fault-tolerance requirements of subtasks of the tasks. The algorithm determines the allocation of subtasks of periodic tasks to sites, the scheduled start times of subtasks allocated to a site, and the schedule for communication along the communication channel(s). Experimental evaluation of the algorithm shows that the heuristics and search techniques incorporated in the algorithm are extremely effective. Specifically, they show that, if a task set can be feasibly allocated and scheduled, the algorithm is highly likely to find it without any backtracking during the search.