Web Performance Testing (WPT)
Course Description
Many testers make huge efforts to test the functionality of Web sites working to tight deadlines with only limited test staff and equipment. The site is released to production and the features work. However, response times are slow in live operation and the site cannot handle peak loads. In addition, the site isn™t robust and cannot routinely recover from errors. If you™ve already been there, or don™t want to go there, this course goes beyond the basics of functionality testing to ensure that your site works in its "live" production environment before users discover problems.
The course is instructor-led with lecture presentations being supported by a realistic case study, based on a fictitious Web site, which allows reinforcement of learning and enhances the understanding process. In addition, various testing tools will be demonstrated.
Target Student
The course is designed for software testers and test managers who will be involved in performance testing of Web sites and applications.
Prerequisites
A good knowledge of Internet architecture and Web software testing. Attendance on the Web Software Testing course would be an ideal prerequisite.
Performance-Based Objectives
Upon successful completion of this course, students will be able to:
Examine performance requirements and ensure that the requirements are realistic and achievable.
Specify what types of performance tests are required and create tests, test cases and test scripts.
Communicate adequately with appropriate technical personnel to ensure that the correct test environments are set up.
Understand the capabilities of performance testing tools and make a significant contribution to tool selection.
Execute performance tests and analyse the results.
Make a contribution to diagnosing performance problems.
Understand how to test a site™s reliability and scalability prior to release.
Course Content
Web Architecture
The big picture - end to end communication
Communication protocol models, the four-layer model
Packets, routers, the domain name system
HyperText Transfer Protocol (HTTP)
Client Internet access (fixed), wired local area networks, Ethernet
Wireless local area networks, client internet access (mobile)
ISP backbones
Firewalls, example firewall architectures, virtual private networks
Example architectures self hosting and data centre
Performance Test Specification
Performance degradation
Prerequisites to performance testing
The general process, when to start performance testing
Categories of performance tests
Single-shot/smoke testing
Load and scalability testing
Stress and hot spot testing
Spike and bounce testing, integrity testing
Defining and selecting test objectives
Response time requirements, user interface responsiveness
Defining the workload, think times, site arrival and abandonment, usage patterns
Client platforms, client internet access speeds fixed and mobile
ISP tiers, user geographic locations, background loads
Preparation
Acquiring the test scripts and data, identifying data requirements and sources of data
Specifying the test environment, selecting the loads to run
Sampling errors, concurrency
Load generation options
Manual load testing
Home-grown load testing software, open source tools
Integrated development environments, Web-only load testing tools
Hosted load testing services, enterprise-class load testing solutions
Network considerations
Load generators, calibration of load generators
Execution
Running the tests, specifying the number of runs
Measuring the load, white-box and black-box measurements
Full-blown and focused testing
Phased load testing
Component level stress tests, infrastructure load tests, architectural load tests
End to end load tests
Analysis
Response time graphs, margins of error
Diagnosing performance problems, troubleshooting strategies
Improving performance
Example analysis data from load testing tools
Scalability
Scalability factors
Scalability testing objectives
Server scalability, Web server scalability
Application server scalability, database server scalability
Server farms and load balancing
Web site mirroring, Web site caching
Reliability and Availability
Testing objectives
Categories of tests
Low resource testing
Endurance testing
Volume testing, peak loading
Network quality of service
Web site failover testing, server failover testing
Parallel and serial dependencies
