Performance Testing Tips and Techniques - PPT

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Performance Testing Tips and Techniques Understanding Operational Profiles Dale L Perry Software Quality Engineering

Transcript of Performance Testing Tips and Techniques - PPT

Page 1: Performance Testing Tips and Techniques - PPT

Performance Testing Tips and Techniques

Understanding Operational Profiles

Dale L PerrySoftware Quality Engineering

Page 2: Performance Testing Tips and Techniques - PPT

2©2005-2006 Collard & Company/SQE V2.2

Performance Profiles

• One of the key activities in performance testing is to decide what type of load or loads to place on the system/application

• There are many variations of performance testing that we can select from so we first have to determine what is needed

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Types Of Performance Testing

• The three most common types of software performance testing include:– Testing which is driven by what we want to

measure– Testing which is based on the source or type

of the load– Testing to stress the system or find its limits

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Understanding Load

• Once we have an idea of what we want to accomplish– The general type of testing we want– What tests we want to run

• Now we have to decide on the volume of activity and the composition of that volume, load (i.e. workload)

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Load (Operational) Profile

• To better simulate the real world, not only should the load size be estimated, but also a profile of the users/activities that make up the load needs to be created

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Test Sample Sizes• Most factors which we want to measure, such as

response time, vary based on many factors; both known and unknown– This means we cannot measure something once but

must sample it several times in order to compute a meaningful average

– How big does the sample need to be? This is a rough rule of thumb for the relationship between sample size and accuracy

Sample AccuracySize (roughly) 30 50% 100 25% 200 10%1,000 3%

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When To Sample – Sampling Errors7 9

Eastern

Central

Mountain

Pacific

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Number And Types Of Users

• The mix of users(events) may vary by time period

• Special events can alter the mix

Browsers

Buyers

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Concurrency

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Think Times

• The time it takes a client (or virtual client) to respond to an application may have a significant impact on the number of clients an application can support– This is a key aspect of concurrency

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Background Load (Noise)

• What additional activities need to be considered to accurately reflect the performance degradation caused by network and other application loads, “background noise”?

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Summary

• A successful software performance test plan starts with knowing what it is you want to accomplish

– What types of tests do you want?

– What loads and mixes are are needed for these tests Operational profile