Low Cost Slack Stealing Method for RM/DM

JOSÉ M. URRIZA; FRANCISCO PAEZ; RICARDO CAYSSIALS; JAVIER DARIO OROZCO; LUCAS S. SCHORB

International Review on Computers and Software

Praise Worthy Prize

Año: 2010 vol. 5 p. 660 - 667

1828-6003

Abstract—Real Time Systems are currently found in millions of devices such as GPS, laptops, cell phones, computers, etc. These systems process real time tasks in conjunction with common tasks. Their coexistence requires methods and techniques that are necessary for the proper function of the heterogeneous system. Slack Stealing methods are an important tool to know how long the real time system tasks can be delayed without affecting its proper operation, and thus assign non real time tasks to the microprocessor. Delaying the execution of real-time tasks in order to reduce the response time of non-real time task could be very usefull in applications such as energy saving, fault tolerance, aperiodic tasks execution, among others. However, slack stealing method proposed in the literatre cannot be implemented during runtime because of its computational complexity. This paper presents a theoretical development that reduces the computational cost of the calculation of the available system slack and an algorithm that makes its implementation feasible during runtime.