Analysis and Improvement of Scheduling Algorithms Based on (m, k)-Firm Constraint

On the basis of the definition of WHRT (weakly hard real-time), this paper summarizes the constraint qualifications of the existing WHRT and scheduling algorithms, places emphasis on the discussion of DBP algorithm and E-DBP algorithm, proposes two concepts according to the deficiencies of the two algorithms, namely total distance of entering invalidation and total distance of aborting invalidation, presents the distance calculation equation, develops TDBP(total distance based priority) algorithm and extends the priority setting methods of DBP and E-DBP further more which solve the problem of the 01 state distributing information ignored in both algorithms. The simulation results indicate that TDBP has reduced the rate of dynamic invalidation and increased the performance of the system, and it also makes the number of received packets in each terminal close to average value.