The priority inversion problem has been detected two decades ago. The decisive ideas to cope with this problem have been published one decade ago. In the meantime the vendors of operating systems and run–time systems have occupied this topic in providing certain protocols in order to avoid priority inversion. However, at a closer look there are considerable differences in the usage and the resu...

The heap-on-top (hot) priority queue data structure 6] improves on the best known times for Dijkstra's shortest path algorithm. It also has very good practical performance and is robust over a wide range of graph types. The heart of Dijkstra's algorithm is a monotone priority queue, that is, a priority queue where no element on the queue ever becomes smaller than the most recently extracted ele...

background priority setting in healthcare is a key determinant of health system performance. however, there is no widely accepted priority setting evaluation framework. we reviewed literature with the aim of developing and proposing a framework for the evaluation of macro and meso level healthcare priority setting practices.   methods we systematically searched econlit, pubmed, cinahl, and ebsc...

This article argues that, contrary to the received view, prioritarianism and egalitarianism are not jointly incompatible theories in normative ethics. By introducing a distinction between weighing and aggregating, the authors show that the seemingly conflicting intuitions underlying prioritarianism and egalitarianism are consistent. The upshot is a combined position, equality-prioritarianism, w...

I start from three premises, roughly as follows: (1) that if possible world x is better than world y for every individual who exists in either world, then x is better than y; (2) that if x has a higher average utility, a higher total utility, and no more inequality than y, then x is better than y; (3) that better than is transitive. From these premises, it follows that equality lacks intrinsic ...

This paper presents the A ected Set Priority Ceiling Protocols (ASPCP) for concurrency control in real-time object-oriented systems. These protocols are based on a combination of semantic locking and priority ceiling techniques. This paper shows that the ASPCP protocols provide higher potential concurrency for object-oriented systems than existing Priority Ceiling protocols, while still boundin...

We describe a decision procedure for a logic that supports 1) finite collections of elements (sets or multisets), 2) the cardinality operator, 3) a total order relation on elements, and 4) min and max operators on entire collections. Among the applications of this logic are 1) reasoning about the externally observable behavior of data structures such as random access priority queues, 2) specify...

In this paper we present a simple and efficient implementation of a min-max priority queue, reflected min-max priority queues. The main merits of our construction are threefold. First, the space utilization of the reflected min-max heaps is much better than the naive solution of putting two heaps back-to-back. Second, the methods applied in this structure can be easily used to transform ordinar...

In this paper, we present an admission control scheme which provides per-flow delay and bandwidth guarantees based solely upon simple class-based strict priority queue-ing. We derive basic properties of the worst-case behaviour in strict priority queueing systems using network calculus. Building upon these properties the flow admission control scheme is devised. The rationale behind this work i...

We study the space requirements of a sorting algorithm where only items that at the end will be adjacent are kept together. This is equivalent to the following combinatorial problem: Consider a string of fixed length n that starts as a string of 0’s, and then evolves by changing each 0 to 1, with the n changes done in random order. What is the maximal number of runs of 1’s? We give asymptotic r...