text: Abstract Scheduling is essentially a decision-making process that enables resource sharing among a number of activities by determining their execution order on the set of available resources. The emergence of distributed systems brought new challenges on scheduling in computer systems, including clusters, grids, and more recently clouds. On the other hand, the plethora of research makes it hard for both newcomers researchers to understand the relationship among different scheduling problems and strategies proposed in the literature, which hampers the identification of new and relevant research avenues. In this paper we introduce a classification of the scheduling problem in distributed systems by presenting a taxonomy that incorporates recent developments, especially those in cloud computing. We review the scheduling literature to corroborate the taxonomy and analyze the interest in different branches of the proposed taxonomy. Finally, we identify relevant future directions in scheduling for distributed systems.
  @cite_141: Static scheduling of a program represented by a directed task graph on a multiprocessor system to minimize the program completion time is a well-known problem in parallel processing. Since finding an optimal schedule is an NP-complete problem in general, researchers have resorted to devising efficient heuristics. A plethora of heuristics have been proposed based on a wide spectrum of techniques, including branch-and-bound, integer-programming, searching, graph-theory, randomization, genetic algorithms, and evolutionary methods. The objective of this survey is to describe various scheduling algorithms and their functionalities in a contrasting fashion as well as examine their relative merits in terms of performance and time-complexity. Since these algorithms are based on diverse assumptions, they differ in their functionalities, and hence are difficult to describe in a unified context. We propose a taxonomy that classifies these algorithms into different categories. We consider 27 scheduling algorithms, with each algorithm explained through an easy-to-understand description followed by an illustrative example to demonstrate its operation. We also outline some of the novel and promising optimization approaches and current research trends in the area. Finally, we give an overview of the software tools that provide scheduling mapping functionalities.
summary: Kwok and Ahmad @cite_141 survey static scheduling algorithms for allocating tasks connected as directed task graphs (DAGs) into multiprocessors. The authors presented a simplified taxonomy for approaches to the problem, as well as the description and classification of @math scheduling algorithms. The DAG scheduling algorithms for multiprocessors have been adapted for scheduling in distributed systems, incorporating intrinsic characteristics of such systems for an enhanced performance. Therefore, Kwok and Ahmad presented static scheduling algorithms for multiprocessors, which are also applicable to distributed systems, and their classification. In this paper we review extensions of those algorithms as well as the their classification by including heterogeneous systems, dynamic scheduling algorithms, scheduling algorithms in modern distributed environments, and new scheduling techniques.