Period-Dependent Initial Values forExactSchedulability TestofRate Monotonic Systems

Real-time systems using RateMonotonic fixed priority scheduling canbechecked forschedulability either by pessimistic schedulability conditions orexacttesting. Exacttesting provides amoreprecise result butcannot always beperformed inpolynomial time. Audsley etal. proposed oneoftheearliest methods byiteratively deriving thejobresponse times. Otherresearchers have improved theefficiency oftheir exact test method byusing different initial values. Allcurrently proposed initial values donotusetherelationship between task periods. In this paperwedefine initial values using thelargest and thesecond largest periods inasystem. Weshowthat the newinitial values cansignificantly improve theexact test.