Study of Load Balancing Issues Based on Intra-Movie Skewness for Parallel Video Servers

In order to avoid the load imbalance problem caused by video popularity, parallel video servers divide video objects into small segments and put them across multiple server nodes. However, due to users’ various viewing time, access numbers of movie segments are quite different. Some segments are more popular than others. This instance is called intra-movie skewness, which may leads to load imbalance among server nodes in parallel video servers. In this paper we analyze and model the intra-movie skewness. Then, a novel data placement strategy, SPS (Symmetrical Pair Scheme), is proposed. It is proved that SPS prevents the impact of intra-movie skewness and has better load balancing performance than traditional round robin data placement, especially in a large-scale parallel video server.