Characterization of blocking time in real-time systems with dynamic priority ceilings

In a single processor real time system, scheduled via the Earliest Deadline First algorithm (EDF), we have accurately characterized the blocking time that each task can encounter when accesses to shared resources are regulated via the Dynamic Priority Ceiling Protocol (DPCP). It is shown that worst case blocking times do not always reach the total duration of the critical sections which produce them. Our characterization allows the real time system designer to attain a higher processor utilization factor while the tasks meet all their deadlines.