World Wide Web(WWW) services have grown to levels where significant delays are expected to happen.Technology like prefetching are likely to help users to personalize their needs ,reducing their waiting times. This pap...World Wide Web(WWW) services have grown to levels where significant delays are expected to happen.Technology like prefetching are likely to help users to personalize their needs ,reducing their waiting times. This paperfirstly describes the architecture of prefetching,then classifies them into three types: based on branch model,based ontree model and others and presents profoundly the basic ideas of some existing prefetching algorithms. Next,severalmodels for controlling the prefetching are introduced. At last ,the trend and course concerning the prefetching algo-rithms are concluded.展开更多
In this paper, a prefetching technique is proposed to solve the performance problem caused by remote data access delay. In the technique, the map tasks which will cause the delay are predicted first and then the input...In this paper, a prefetching technique is proposed to solve the performance problem caused by remote data access delay. In the technique, the map tasks which will cause the delay are predicted first and then the input data of these tasks will be preloaded before the tasks are scheduled. During the execution, the input data can be read from local nodes. Therefore, the delay can be hidden. The technique has been implemented in Hadoop-0. 20.1. The experiment results have shown that the technique reduces map tasks causing delay, and improves the performance of Hadoop MapRe- duce by 20%.展开更多
文摘World Wide Web(WWW) services have grown to levels where significant delays are expected to happen.Technology like prefetching are likely to help users to personalize their needs ,reducing their waiting times. This paperfirstly describes the architecture of prefetching,then classifies them into three types: based on branch model,based ontree model and others and presents profoundly the basic ideas of some existing prefetching algorithms. Next,severalmodels for controlling the prefetching are introduced. At last ,the trend and course concerning the prefetching algo-rithms are concluded.
文摘In this paper, a prefetching technique is proposed to solve the performance problem caused by remote data access delay. In the technique, the map tasks which will cause the delay are predicted first and then the input data of these tasks will be preloaded before the tasks are scheduled. During the execution, the input data can be read from local nodes. Therefore, the delay can be hidden. The technique has been implemented in Hadoop-0. 20.1. The experiment results have shown that the technique reduces map tasks causing delay, and improves the performance of Hadoop MapRe- duce by 20%.
