Modern embedded systems are often required to execute under stringent real-time constraints to satisfy high performance requirements. When the available computational resources are scarce, an efficient implementation of the scheduler is of crucial importance for containing system costs. In this paper, we present an efficient implementation of the Earliest Deadline First (EDF) scheduler, which i...

Real-time systems power safety-critical applications that require strong isolation among each other. Such needs to be enforced at two orthogonal levels. On the micro-architectural level, this mainly involves avoiding interference through states, such as cache lines. algorithmic is usually achieved by adopting real-time partitions reserve resources for application. Implementations of are often c...

Recent work showed that semi-partitioned scheduling can achieve near-optimal schedulability performance, is simpler to implement compared to global scheduling, and less heavier in terms of runtime overhead, thus resulting in an excellent choice for implementing real-world systems. However, semi-partitioned scheduling typically leverages an off-line design to allocate tasks across the available ...

Over the years, the preemptive periodic constrained-deadline task model [9] has proven remarkably useful for the modeling of recurring processes that occur in hard real-time computer application systems, where the failure to satisfy any constraint may have disastrous consequences. The problem of scheduling such tasks upon a single processor (CPU) so that all the deadlines are met has been widel...

In [1], the author empirically compared EDF (Earliest Deadline First) and RM (Rate Monotonic) scheduling algorithms and made a few EDF preemption behavior observations based on data obtained from the first 1,000 time units of scheduling activities. However, based on test settings given in [1], the first 1,000 time units occupies only a small percentage of the entire task set’s hyper-period. We ...

Generalized Processor Sharing (GPS) has gained much popularity in recent years as a simple and effective scheduling mechanism for the provisioning of Quality of Service (QoS) in emerging high-speed networks. For supporting deterministic end-to-end delay guarantees, GPS is known to be sub-optimal in comparison to the Earliest Deadline First (EDF) scheduling discipline; nevertheless it is often p...

EDF is a classic dynamic embedded realtime multi-task scheduling algorithm. In an embedded soft real-time system, the deadline missing ratio is an important metric to evaluate system performance. When an embedded soft realtime system is overloaded, EDF algorithm is not effective. Considering the unsteadiness and unpredictability of a practical task running environment due to the unsteadiness of...

This paper presents a heavy-traffic analysis of the behavior of a single-server queue under an Earliest-Deadline-First (EDF) scheduling policy, in which customers have deadlines and are served only until their deadlines elapse. The performance of the system is measured by the fraction of reneged work (the residual work lost due to elapsed deadlines), which is shown to be minimized by the EDF po...

With the growing complexity of modern embedded real-time systems, scheduling and managing of resources has become a daunting task. While scheduling and resource management for internal events can be simplified by adopting a commonplace real-time operating system (RTOS), scheduling and resource management for external events are left in the hands of the programmer, not to mention managing resour...

Restricted migration of periodic and sporadic tasks on uniform heterogeneous multiprocessors is considered. Migration between different processors of a multiprocessor causes overhead that may be prohibitively high for real-time systems, where accurate timing is essential. Nonetheless, periodic tasks, which generate jobs at regular intervals, may be able to migrate without causing overhead if th...