【摘要】 通过把赤字带宽引入到流媒体文件流行度中,定义了一种新的流媒体文件的流行度,以该流行度为依据,确定需要复制的流媒体文件,将节点按综合性能指标进行排序,把副本放置在综合性能高的节点上。在副本放置空间不足时需要进行副本替换,替换掉副本实际数量与期望数量之比中比值最大的文件,以复制新的文件。实验表明,和比例复制算法相比,本算法的工作负载更早进入稳态,平均提前了总仿真时间的13%。稳态时,工作负载更小,工作负载是比例复制算法的33.3%;达到流媒体文件请求速率的节点数量比比例复制算法的节点数量平均多1‰左右;同时在暂态时,本算法的波动更加平稳。更多还原

【Abstract】 In this paper, a new formula of popularity was proposed. It included the term deficit bandwidth and was based on the new popularity. Those streaming media files which need to be replicated were determined. A concept named comprehensive performance indicators was proposed. Peers were sorted by their comprehensive performance indicators and those peers with high comprehensive performance indicators had priority to place these popular files. Replacement algorithm would be carried out if there was no enough space to cache the new file, and the file which had largest ratio of its duplicates to the desired duplicates would be replaced by the new file. Experimental results show that the workload of the proposed algorithm, compared with proportional replication algorithm, is in steady conditions earlier about 13 % in advance and is smaller. Its workload in steady-state condition is about33. 3 % of the workload of the proportional replication algorithm. Meanwhile, more of one in a thousand peers has the desired requested rates in steady-state. Besides, the proposed algorithm has more stationary transient process.更多还原