Abstract
In a world where many users rely on the Web for up-to-date personal and business information and transactions, it is fundamental to build Web systems that allow service providers to differentiate user expectations with multi-class Service Level Agreements (SLAs). In this paper we focus on the server components of the Web, by implementing QoS principles in a Web-server cluster that is, an architecture composed by multiple servers and one front-end node called Web switch. We first propose a methodology to determine a set of confident SLAs in a real Web cluster for multiple classes of users and services. We then decide to implement at the Web switch level all mechanisms that transform a best-effort Web cluster into a QoS-enhanced system. We also compare three QoS-aware policies through experimental results in a real test-bed system. We show that the policy implementing all QoS principles allows a Web content provider to guarantee the contractual SLA targets also in severe load conditions. Other algorithms lacking some QoS principles cannot be used for respecting SLA constraints although they provide acceptable performance for some load and system conditions.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
T. Abdelzaher, K. Shin and N. Bhatti, Performance guarantees for Web server end-systems: A control-theoretical approach, IEEE Transactions on Parallel and Distributed Systems 13(1) (2002) 80–96.
J. Almeida, M. Dabu, A. Manikntty and P. Cao, Providing differentiated levels of service in Web content hosting, in: Proceedings of Workshop on Internet Server Performance, Madison, WI (June 1998).
Apache Server Foundation, Apache HTTP Server Project, http://www. apache.org.
M. Aron, P. Druschel and W. Zwaenepoel, Cluster reserves: A mechanism for resource management in cluster-based network servers, in: Proceedings of ACM Sigmetrics 2000, Santa Clara, CA (June 2000).
G. Banga, P. Druschel and J.C. Mogul, Resource containers: A new facility for resource management in server systems, World Wide Web 2(1-2) (1999).
P. Barford, A. Bestavros, A. Bradley and M.E. Crovella, Changes in Web client access patterns: Characteristics and caching implications, World Wide Web 2(1-2) (March 1999) 15–28.
N. Bhatti and R. Friedrich, Web server support for tiered services, IEEE Network 13(5) (September/October 1999) 64–71.
J. Bruno, E. Gabber, B. Ozden and A. Silberschatz, The Eclipse operating system: Providing quality of service via reservation domains, in: Proceedings of USENIX 1998 Conference, Berkeley, CA (June 1998).
V. Cardellini, E. Casalicchio, M. Colajanni and M. Mambelli, Web switch support for differentiated services, ACM Performance Evaluation Review 29 (2001).
V. Cardellini, E. Casalicchio, M. Colajanni and P. Yu, The state of the art in locally distributed web-server systems, IBM Research Report RC 22209, Yorktown Heights, NY (October 2001).
V. Cardellini, E. Casalicchio, M. Colajanni and P. Yu, The state of the art in locally distributed web-server system, ACM Computing Surveys 34(2) (June 2002).
H. Chen, X. Chen and P. Mohapatra, An admission control scheme for predictable server response time for Web accesses, in: Proceedings of the 10th World Wide Web Conference, Hong Kong (May 2001).
L. Cherkasova and P. Phaal, Session based admission control: A mechanism for improving performance of commercial Web sites, in: Proceedings International Workshop on Quality of Service, London (June 1999).
A. Cohen, S. Rangarajan and H. Slye, On the performance of TCP splicing for URL-aware redirection, in: Proceedings of USENIX Symposium on Internet Technologies and Systems, Boulder, CO (October 1999).
M.E. Crovella and A. Bestavros, Self-similarity in World Wide Web traffic: Evidence and possible causes, IEEE/ACM Transactions on Networking 5(6) (December 1997) 835–846.
A. Demers, S. Keshav and S. Shenker, Analysis and simulation of a fair queueing algorithm, in: Proceedings of ACM Sigcomm 1989, Austin, TX (September 1989).
R. Engelschall, Load balancing your web site, Web Techniques Magazine 3 (May 1998).
HP Labs, WebQoS, http://www.internetsolutions.enterprise.hp.com/ webqos.
V. Kanodia and E.W. Knightly, Multi-class latency-bounded Web services, in: Proceedings of International Workshop on Quality of Service, Pittsburgh, PA (June 2000).
D. Krishnamurthy and J. Rolia, Predicting the QoS of an electronic commerce server: Those mean percentiles, in: Proceedings of Workshop on Internet Server Performance, Madison, WI (June 1998).
K. Li and S. Jamin, A measurement-based admission-controlled Web server, in: Proceedings of IEEE Infocom 2000, Tel Aviv, Israel (March 2000).
Z. Liu, M. Squillante and J. Wolf, On maximizing service-level-agreement profits, in: Proceedings of 3rd ACM Conference on Electronic Commerce, Tampa, FL (October 2001).
V.S. Pai, M. Aron, G. Banga, M. Svendsen, P. Druschel, W. Zwaenepoel and E. Nahum, Locality-aware request distribution in cluster-based net-work servers, in: Proceedings of 8th ACM Conference on Architectural Support for Programming Languages and Operating Systems, San Jose, CA (October 1998).
R. Pandey, R. Barnes and J.F. Olsson, Supporting quality of service in HTTP servers, in: Proceedings of ACM Symposium on Principles of Distributed Computing, Puerto Vallarta, Mexico (June 1998).
N. Vasiliou and H.L. Lutfiyya, Providing a differentiated quality of service in a World Wide Web server, ACM Performance Evaluation Review 28(2) (September 2000) 22–28.
H. Zhu, H. Tang and T. Yang, Demand-driven service differentiation in cluster-based network servers, in: Proceedings of IEEE Infocom 2001, Anchorage, Alaska (April 2001).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Andreolini, M., Casalicchio, E., Colajanni, M. et al. A Cluster-Based Web System Providing Differentiated and Guaranteed Services. Cluster Computing 7, 7–19 (2004). https://doi.org/10.1023/B:CLUS.0000003940.34740.be
Issue Date:
DOI: https://doi.org/10.1023/B:CLUS.0000003940.34740.be