为了解决Min-Min调度算法中存在的负载不平衡问题,提高集群系统的负载均衡性,该文提出了一种基于Min-Min极限下压算法的负载模糊分类与局部重调度算法(Load fuzzy classification and local re-schedule algorithm,LFC-LRA)。引入模糊...为了解决Min-Min调度算法中存在的负载不平衡问题,提高集群系统的负载均衡性,该文提出了一种基于Min-Min极限下压算法的负载模糊分类与局部重调度算法(Load fuzzy classification and local re-schedule algorithm,LFC-LRA)。引入模糊分类的思想,根据各节点的负载大小,将节点分成三种类型:重负载、中负载和轻负载;对负载较重和较轻的节点进行重新调度,使用Min-Min极限下压算法压缩这些节点的任务完成时间,改善算法的负载失衡问题。实验结果表明:改进后的算法具有较好的负载均衡性,能有效地提高资源的利用率,降低系统的任务完成时间。展开更多
When sampling from a finite population there is often auxiliary information available on unit level. Such information can be used to improve the estimation of the target parameter. We show that probability samples tha...When sampling from a finite population there is often auxiliary information available on unit level. Such information can be used to improve the estimation of the target parameter. We show that probability samples that are well spread in the auxiliary space are balanced, or approximately balanced, on the auxiliary variables. A consequence of this balancing effect is that the Horvitz-Thompson estimator will be a very good estimator for any target variable that can be well approximated by a Lipschitz continuous function of the auxiliary variables. Hence we give a theoretical motivation for use of well spread probability samples. Our conclusions imply that well spread samples, combined with the Horvitz- Thompson estimator, is a good strategy in a varsity of situations.展开更多
文摘为了解决Min-Min调度算法中存在的负载不平衡问题,提高集群系统的负载均衡性,该文提出了一种基于Min-Min极限下压算法的负载模糊分类与局部重调度算法(Load fuzzy classification and local re-schedule algorithm,LFC-LRA)。引入模糊分类的思想,根据各节点的负载大小,将节点分成三种类型:重负载、中负载和轻负载;对负载较重和较轻的节点进行重新调度,使用Min-Min极限下压算法压缩这些节点的任务完成时间,改善算法的负载失衡问题。实验结果表明:改进后的算法具有较好的负载均衡性,能有效地提高资源的利用率,降低系统的任务完成时间。
文摘When sampling from a finite population there is often auxiliary information available on unit level. Such information can be used to improve the estimation of the target parameter. We show that probability samples that are well spread in the auxiliary space are balanced, or approximately balanced, on the auxiliary variables. A consequence of this balancing effect is that the Horvitz-Thompson estimator will be a very good estimator for any target variable that can be well approximated by a Lipschitz continuous function of the auxiliary variables. Hence we give a theoretical motivation for use of well spread probability samples. Our conclusions imply that well spread samples, combined with the Horvitz- Thompson estimator, is a good strategy in a varsity of situations.