Scheduling real-time computations with extended deadlines

In many applications, a real-time job allows part of its computation to be finished after its primary deadline but before its extended deadline. The authors study the scheduling issues for real-time computations with extended deadlines. They call the part of a computation which must be completed before the primary deadline its hard part, and the rest its soft part. Two variations of this problem are studied. In the first model, the system receives a penalty for each late soft part. In the second model, there is an extra computation overhead for each late soft part. For each model, algorithms to produce a feasible schedule are presented.<>