We present new admission tests for periodic real-time threads with explicitly stated deadlines scheduled according to the earliest deadline first (EDF) algorithm. In traditional real-time periodic scheduling, the deadline of a periodic thread is conventionally the end of the current period. In contrast, our tests support periodic threads in which the deadline may be earlier than the end of the ...

OF THE THESIS End-to-End Delay Analysis for Wireless Control Networks under EDF Scheduling by Chengjie Wu Master of Science in Computer Science Washington University in St. Louis, August 2013 Research Advisor: Professor Chenyang Lu Process industries are starting to adopt multi-hop and multi-channel wireless control networks (WCNs) for process control applications. To meet the stringent real-ti...

Many sensor-based control systems are dynamically changing, and thus require a flexible scheduler. The rate monotonic (RM) real-time scheduling algorithm does not support such dynamic systems very well. On the other hand, with earliest-deadline-first (EDF) and minimum-laxity-first (MLF) dynamic scheduling algorithms, a transient overload in the system may cause a critical task to fail, which is...

 This paper proposes an analytical method to evaluate the delay violation probability of traffic flows with statistical Quality-of-Service (QoS) guarantees in an Earliest Deadline First (EDF) scheduler. The statistical QoS targets for each service class are expressed in terms of a delay threshold and delay violation probability. We study both cases isolated nodes and end-to-end paths comprisin...

The earliest-deadline-first (EDF) scheduling algorithm, while not optimal for globally-scheduled hard real-time systems, can support any feasible task system with bounded lateness. Furthermore, global-EDF-like (GEL) scheduling algorithms, which prioritize jobs by assigning them fixed priority points based on per-task relative priority points, have been shown to share this same property. Some su...

This paper develops a framework for statistically guaranteeing end-to-end delay bounds to envelopeconstrained connections transporting real-time traffic in a network of switches employing the Earliest Deadline First (EDF) packet scheduling scheme in conjunction with per-hop traffic shaping. The performance of an isolated EDF scheduler fed by markovian sources has been studied earlier in the lit...

Worldwide interoperability for Microwave Access (WiMAX) is based on the IEEE 802.16 standard. This technology provides broadband wireless last-mile access in a Metropolitan Area Network (MAN). The IEEE 802.16-2004 standard (i.e. Fixed WiMAX) provides specification for the Medium Access Control (MAC) and Physical (PHY) layers for WiMAX. A critical part of the MAC layer specification is schedulin...

| Many real-time applications have very tight time constraints which couldn't be met by disk resident databases. For those applications, main memory database where entire database is stored in main memory is the proper choice. It has been shown that coarse-granule locking is better than ne-granule locking for main-memory databases. Coarse-granule locking makes it easy to extract data access pat...

We describe a mechanically-checked proof of the optimality of earliest-deadline-rst (EDF) schedulers on periodic tasks accomplished using the Nqthm theorem prover. We present a formalization of the theorem and discuss why the machine-checked proof is both more complex and more reliable than a corresponding informal proof.