James H. Anderson

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Real-time scheduling algorithms for multiprocessor systems have been the subject of considerable recent interest. For such an algorithm to be truly useful in practice, support for semaphore-based locking must be provided. However, for many global scheduling algorithms, no such mechanisms have been proposed. Furthermore, in the partitioned case, most prior(More)
Real-time multiprocessor systems are now commonplace. Designs range from single-chip architectures, with a modest number of processors, to large-scale signal-processing systems, such as synthetic-aperture radar systems. For uniprocessor systems, the problem of ensuring that deadline constraints are met has been widely studied: effective scheduling(More)
This paper is concerned with synchornization under read/write atomicity in shared memory multi-processors. We present a new algorithm forN-process mutual exclusion that requires only read and write operations and that hasO(logN) time complexity, where “time” is measured by counting remote memory references. The time complexity of this algorithm is better(More)
This article considers the use of lock-free shared objects within hard real-time systems. As the name suggests, <italic>lock-free</italic> shared objects are distinguished by the fact that they are accessed without locking. As such, they do not give rise to priority inversions, a key advantage over conventional, lock-based object-sharing approaches. Despite(More)
We consider the use of the earliest-deadline-first (EDF) scheduling algorithm in soft real-time multiprocessor systems. In hard real-time systems, a significant disparity exists between EDF-based schemes and Pfair scheduling (which is the only known way of optimally scheduling recurrent real-time tasks on multiprocessors): on M processors, all known EDF(More)
We present a real-time, Linux-based testbed called LITMUS, which we have developed for empirically evaluating multiprocessor real-time scheduling algorithms. We also present the results from such an evaluation, in which partitioned earliest-deadline-first (EDF) scheduling, preemptive and nonpreemptive global EDF scheduling, and two variants of the global PD(More)
There has been much recent interest in multiprocessor Pfair and ERfair scheduling algorithms. Under Pfair scheduling, each task is broken into quantum-length subtasks, each of which must execute within a \window" of time slots. These windows divide each period of a task into potentially overlapping subintervals of approximately equal length. \Early-release"(More)
BJÖRN B. BRANDENBURG: Scheduling and Locking in Multiprocessor Real-Time Operating Systems (Under the direction of James H. Anderson) With the widespread adoption of multicore architectures, multiprocessors are now a standard deployment platform for (soft) real-time applications. This dissertation addresses two questions fundamental to the design of(More)