Web Transaction Analysis and
Optimization (TAO)
Pankaj K. Garg, Ming Hao, Cipriano Santos,
Hsiu-Khuern Tang, Alex Zhang
Software Technology Laboratory
HP Laboratories Palo Alto
HPL-2002-45
March 4 th , 2002*
E-mail: garg@hpl.hp.com
software
performance
monitoring,
Web
performance
tuning,
application
response
monitoring,
software
performance
modeling
Web user interactions start at a client (a browser on an access device)
and flow through several software components connected via digital
networks. While the business world is fascinated with the range of
possibilities for such E-transactions, the underlying technology opens
up several new challenges for managing the performance, availability,
and reliability of the enabling software components. Several studies
have shown that poor response times for Web user interactions can
significantly impact the business values--slow Web transactions can
have strong implications on brand-name, customer acquisition and
loyalty, and purchasing behavior of customers.
In the TAO project, we are developing metrics, models, and
infrastructure to effectively manage the performance of Web
applications. We use WebMon, a novel instrumentation tool to obtain
transaction -level data from web interactions, from end-user and
system component perspectives. Our analysis techniques help
determine important segments of users and their web interactions.
The analysis is embedded in visualization and optimization modules,
enabling efficient reporting for system and business administrators,
and automated resource scheduling and planning. In this paper we
present an overview of the TAO project, and highlight some of its novel
aspects, e.g., use of pixel-bar charts, web request classification, and
integrated demand and capacity planning.
* Internal Accession Date Only
 Copyright Hewlett-Packard Company 2002
Approved for External Publication
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