(m,k) firm Scheduling of Real-Time Transactions with Concurrency Control

This paper presents a multi-class scheduling algorithm for real-time transactions combining scheduling and concurrency control. The proposed algorithm, DBP_CC (distance based priority and concurrency control) offers service differentiation and QoS guarantees by specifying several (m,k) firm constraints giving the degree of missed deadlines that the system can tolerate for each class. When extracting a transaction, DBP_CC takes into account resource availability so that the execution of the concurrency control algorithm doesn´t change the transactions schedule. Simulation results show that DBP_CC can achieve a significant performance even in overload situations.