Request Scheduling for Differentiated QoS at Website Gateway
With the explosive growth of Web traffic, the load on a Web server becomes heavier, leading to the longer user-perceived latency. Website operators would like to employ service differentiation to offer better throughput and shorter user-perceived latency to some specific users. This paper presents an HTTP request scheduling algorithm deployed at the website gateway to enable the Web quality of service without any modification to client or server software. A variation of the deficit round robin scheduling algorithm and a window control mechanism are presented to decide the order and the releasing time of requests, respectively. The order is decided by the response size of the requests and the pre-defined service weights. The ratio of the bandwidth throughput of the service classes is determined by the weights, whereas the releasing time is decided by the service rate of the Web server. The evaluation reveals the scheduling algorithm can provide service differentiation and improve server throughput and user-perceived latency.
KeywordsSchedule Algorithm Page Size Response Size Server Prober Request Schedule
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- 1.Mills, P., Loosley, C.: A performance Analysis of 40 e-Business Web Sites. CMG Journal of Computer Resource Management (102) (2001)Google Scholar
- 2.Braden, R., Clark, D., Shenker, S.: Integrated Services in the Internet Architecture: an Overview, IETF RFC 1633 (1994), http://www.rfc-editor.org/rfc/rfc1633.txt
- 3.Blake, S., Black, D., et al.: An Architecture for Differentiated Services, IETF RFC 2475 (1998), http://www.rfc-editor.org/rfc/rfc2475.txt
- 4.Braden, R., Zhang, L., et al (eds.): Resource ReSerVation Protocol (RSVP) – Version 1 Functional Specification, IETF RFC 2205 (1997), http://www.rfc-editor.org/rfc/rfc2205.txt
- 5.Almeida, J., Dabu, M., Manikutty, A., Cao, P.: Providing Differentiated Levels of Service in Web Content Hosting. In: Proccedings of the 1998 Workshop on Internet Server Performance (1998)Google Scholar
- 6.Pandey, R., Barnes, J.F., Olsson, R.: Supporting Quality of Service in HTTP Servers. In: Proceedings of the Seventeenth Annual ACM Symposium on Principles of Distributed Computing, pp. 247–256 (1998)Google Scholar
- 12.The Apache HTTP Server Project, http://httpd.apache.org/