Dynamic Workload Partition on Parallel Medical Image Reconstruction Algorithm in Computational Grid Environments

• Main Authors: Chien-Yang Yu, 余乾揚
• Other Authors: Nai-Wei Lo
• Format: Others
• Language: en_US
• Published: 2007
• Online Access: http://ndltd.ncl.edu.tw/handle/c83fpw

碩士 === 國立臺灣科技大學 === 資訊管理系 === 95 === Parallel computing has an issue that every computing node starts to execute an iteration round at the same time until every node is done at that round. Ideally in a cluster computing environment, the hardware of all nodes are the same; however, there are different resources which form a Grid. Therefore, if users want to execute parallel program in Grid, the work loads become more important regarding to the distribution of task amount. For instance, a task is divided into several smaller tasks, and three smaller tasks will be executed on different computational resources. Because of inequality in computing power and/or network bandwidth, some resources may finish the tasks sooner than the others. The fastest finished node has to wait until the other nodes also finished The issue in parallel computing as previously mentioned is that computing nodes need to wait each other in every execution round. The purpose of this study is to find the best workload distribution for each node, and distribute the suitable amount of tasks during the execution period of each round. In this research, OSEM and COSEM-ML were chosen for experiments. Both of them are algorithms of medical image reconstruction.