Autonomic Pervasive Systems Sukumar Ghosh Professor, Department of Computer Science The University of Iowa The presence of pervasive systems is taken for granted – only its absence becomes noticeable. So maximize availability and reliability. Failures are perturbations are like regular events. Self-management is crucial, which is the essence of autonomic systems. In addition to the known self-* properties, we work on implementing self-immunity, graceful degradation, and fault-containment. 1

Some current work Self-immunity Self-immune systems detect, profile, and then predict failures. Based on the prediction, they proactively invoke remedial actions, so that eventually the failure becomes a non-event. Self-immune systems learn. Graceful degradation Failure? Never give up! Find out what minimal service the system can provide. Make the system spontaneously gravitate to a degraded mode, and later spontaneously restore full functionality when the fault is repaired. Fault-containment Small failures can have a domino effect. Never let that happen. The system must contain the effect of minor failures, both in space and in time.