SEGREGATION SCHEDULING POLICY IN WEB CLUSTER SERVERS

Discussed in this paper is the relationship between the performance of web cluster servers and the scheduling policies using a queuing theory method. The result is that the segregation scheduling policy, in which static requests are directed to some back-end servers and dynamic requests are directed to the other servers, is better than the mixture scheduling policy in which both kinds of requests are uniformly directed to all back-end servers. The tests through SPECweb99 further confirm that when the load parameter is set to 120 connections, the web cluster servers adopting the segregation scheduling policy can improve the performance by 22.5% with finished 63 conforming connections, while the ones adopting the mixture scheduling policy can only finish 36 conforming connections.