Fine-Grained Object Based Load Distribution An Experiment with Load Distribution in Guide-2 Master Thesis

Load distribution is commonly recognized as a useful technique to improve the performance of a distributed system. Much of the previous work on load distribution is performed in the context of process based operating systems executing on autonomous workstations. In this thesis we examine load distribution in the context of ne-grained object based operating systems and describe the design and implementation of a load distribution facility in one such system. Our load distribution facility distributes groups of objects to avoid that some nodes in the system are idle while others are overloaded. We use this load distribution facility to experiment with ne-grained load distribution based on objects. These experiments show that performance may be harmed by distribution of small groups of objects, but that distribution of larger groups of objects may signi cantly improve the performance of the system. Resum e Belastningsudj vning er en anerkendt metode til at forbedre ydeevnen i distribuerede systemer. Hovedparten af den hidtidige forskning indenfor dette omr ade har fokuseret p a traditionelle procesbaserede operativsystemer, hvor hele processer yttes for at udj vne belastningen i et netv rk af arbejdsstationer. Dette speciale behandler belastningsudj vning foretaget i distribuerede objektbaserede systemer og beskriver design og implementation af en belastningsudj vner i s adan et system. Denne belastningsudj vner benytter grupper af objekter til at fordele arbejdet i systemet, s aledes at ingen maskiner er ledige samtidigt med at andre maskiner er overbelastede. Belastningsudj vneren benyttes til at eksperimentere med nkornet belastningsudj vning baseret p a objekter. Disse eksperimenter viser at systemets ydeevne kan forringes n ar sm a grupper af objekter benyttes til belastningsudj vning, mens st rre grupper af objekter kan medf re betragtelige forbedringer af ydeevnen. 3