Ανάλυση αλγορίθμων χρονοδρομολόγησης σε περιβάλλοντα υπολογιστικού νέφους
Scheduling algorithms in cloud computing environments
Τσετσενέκος, Ιάσων - Χαράλαμπος Π.
Scheduling is an integral part of information technology (ΙΤ) as it is applied to operating systems, aiming on task allocation. The allocation is being managed by scheduling algorithms. Furthermore, cloud computing technology has emerged in the world of computer science where most of the applications are based on it. Main characteristic of this technology is the reusability of computational resources which is achieved by scheduling algorithms. The subject of this thesis is the analysis and demonstration of scheduling algorithms that are used in cloud computing. In the first chapter cloud computing technology is described along with the applications that are based on it. The mentioned subjects are the characteristics and the services that are offered in the existing platforms, as well as the security issues that may arise. In the second chapter, virtualization types are introduced and their association with cloud computing. Furthermore, virtualization architectures are presented, as well as the entities that compose it. In the third chapter, the scheduling problem and its types are being presented, along with workflows. In the fourth chapter, examples of scheduling algorithms are presented, as long as the advantages and the disadvantages between them. The subjects of these algorithms vary as they aim to improve different scheduling problems. At last, in the fifth chapter, simulation of some of the aforementioned algorithms is performed with the help of WorkflowSim platform. The results show their behavior, in terms of execution time and resource allocation under different circumstances.