【作者】 朱江；

【导师】 任长明；

【作者基本信息】 天津大学 ， 计算机软件与理论， 2004， 硕士

【摘要】 网格是构筑在互联网上的一种新兴技术,正成为新一代的网络基础设施,网格的研究是目前新的研究热点。网格的目的是把网络的资源有效地整合起来,实现资源的跨组织,跨地域的动态共享,因此对网格资源进行有效的管理是网格的一个关键任务。网格上的资源数量巨大,同时资源还具有动态特性,即资源的状态在随时发生变化。为了让用户能够有效的使用资源,网格资源管理系统必须周期性地对资源状态信息进行更新,以确保资源信息的准确性和有效性。大量的资源更新信息会对网络产生负担,现有的资源更新策略采用降低更新频率策略和数据变化更新策略,降低更新频率策略可以减少资源信息更新的次数,从而减少网络上传输的更新信息的数量,但是其更新频率还是要有一个限度,否则,网格资源管理系统所管理的资源信息和实际的资源状态会有很大的差异,导致用户对资源的使用失效。数据变化更新策略是在资源状态发生变化时通知资源信息中心更新数据。由于网格上大量资源的状态随时在发生变化,资源频繁地发出通知信息和资源状态信息,所以采用这种方法的效果不是很好。事实上,资源状态发生变化时,有时并不会影响用户的使用,这种情况下不需要更新信息;只有资源状态变化幅度超过一定范围时,才会影响用户的使用,此时信息需要更新。基于此,在数据变化更新策略的基础上,我们提出了一种改进的资源更新策略:如果资源状态信息的变化超过了一定的幅度,资源才发出信息更新通知。我们采用模拟实验对改进的资源信息更新策略进行验证,实验结果表明,使用改进的策略可以有效地减少网络上数据的传输量。最后,我们使用OGSI规范实现了改进的资源信息更新策略。更多还原

【Abstract】 Grid is a new techonogy that build on World Wide Web, it is being a newgeneration of network infrastructure. Research on Grid is becoming a new hotresearch area in the world. The goal of the Grid is to intergrate the resources in thenetwork effectively, to realize the dynamic resources sharing across organization andarea. So it’s an important task for the Grid to manage the resources in the Grid. Thereare numerous resources in the Grid and the resources are dynamic, that is the state ofthe resources are changed momentarily. To use the resources effectively , the Gridresouce management system must update the state information of resourcesperiodically. The numerous state information produced by the changed state ofresources will increase the burden of the network. Some policies are taken to avoidthis, as decrease the update frequence and update when the state is changed. Thepolicy of decrease the update frequence can reduce the messages transferred in thenet by reducing the times of update. But if the update frequence is too low , theresource state information that managed by the Grid Resource Management Systemdisgree wiht the real resource state. Then the user will not use the resourceeffectively.The policy of update with data changing meant that the resource willnotify the information center when the state value is changed. There are numerousresources that change at any moment and the notifications will be flooding. In fact, ifthe changed state value doesn’t affect the user who use the resource correctly, theresource need not to send out notification even its state is changed. When the changedstate exceed the range of the specificied data, the resource will send out thenotification. That is the difference with the policy of update with data changing. Wecall this policy as improved policy of resource state update. This work isdemonstrated by simulation experiment. Finally we implement the policy with OGSIspecification.更多还原