Artifact:  Workload Analysis Model

Workload Analysis Model	A model that identifies one or more workload profiles that are deemed to accurately define a system state of interest in which evaluation of the software and/ or it's operating environment can be undertaken. The workload profiles represent candidate conditions to be simulated against the Target Test Items under one or more Test Environment Configurations.
UML Representation:	There is no UML representation for this artifact.
Role:	Test Analyst
Optionality/ Occurrence:	One or more artifacts. Mainly relevant when system load, system performance or system stress testing is to be conducted.
Enclosed in:	Optionally, some aspects of the Workload Analysis Model can be encapsulated within the Iteration Test Plan
Templates:	Other
Examples:
Reports:
More Information:	Guidelines:Workload Analysis Document Checkpoints:Workload Analysis Model
Purpose Brief Outline Properties Timing Responsibility Tailoring

Input to Activities:  Implement Test Analyze Test Failure Determine Test Results Develop Test Guidelines Define Test Environment Configurations Define Testability Elements Define Test Details

Output from Activities:  Define Test Details

Purpose

The Workload Analysis Model attempts to accurately define the loading conditions under which the Target Test Items must operate within their Target Configuration Environment. The main objective is to define a realistic representative workload that allows performance risks to be accurately assessed. Typically determined by analyzing anticipated or existing actor characteristics, end-user's business statistics (use cases), etc.

Brief Outline

1. Introduction

Identifies the purpose, background, and objectives of the performance testing within this project.

2. System Attributes and Variables

Identifies the attributes and variables of the system that uniquely identify the workload for the system being modeled.

4. Actor Definitions

Identifies classes of external clients whose use-case sceanrios will need to be modeled to simulate / emulate loads on the system-under-test. Additionally this section identifies the proportion to which any actor comprises the load for a performance test.

7. Actor Attributes

Identifies the attributes and variables of each actor that uniquely identify the different characteristics of the external clients of the system. For each actor, identifies information such as human or non-human, data-feed rate, think time, transaction style, transaction complexity and behaviour patterns characterizing the variability in end-user interaction with the system.

6. Actor Work Profile

Identifies the specific use-case scenarios executed by an actor and the percentage of time or proportion of effort spent by the actor executing the use-case scenarios to accomplish their total business responsibilities.

3. Work Load Profile

For a given profile, identifies the number of external clients being simulated / emulated during the test, including the number, type and distribution of the transactions. A profile may be defined in terms of "peak load", "average load" and so on.

5. Measurements and Criteria

Identifies the measurement and criteria to be used to evaluate successful achievement of the identified performance objectives. Measurements typically include response time limits or throughput capacity.

8. Remote Terminal Emulation Requirements

Identifies the requirements and constraints necessary to be addressed in creating a Test Environment Configuration that is acceptable for implementing and executing the performance testing.

Properties

There are no UML representations for these properties.

Timing

The Workload Analysis Model should be initially outlined as early as possible, preferably in the Inception phase, with ongoing refinement and detailed definition as needed during the Elaboration phase.

While the Workload Analysis Model may be refined or revised during each Iteration throughout the remainder of the lifecycle, it's good practice to conduct as much of the testing as possible that relates to this artifact in the Elaboration phase. While some system load and performance testing work may continue throughout the project, it is likely any significant defects or required changes identified as a result of these tests will not be practical or affordable if the results are delivered much later than early in the Construction phase.

Responsibility

The Test Analyst role is primarily responsible for this artifact. The responsibilities are split into two main areas of concern:

The primary set of responsibilities covers the following design and implementation issues:

• Eliciting the information required to formulate the Workload Analysis Model.
• The Workload Analysis Model accurately reflects the workload and end-user characteristics of the system being tested.
• To understand the goals of the performance/ load tests and present this accurately and reliably.
• To identify and describe the key use case flows and conditions which best duplicate the end-user’s core business functions, in terms of the test focus. The Workload Analysis Model should also identify the interval being simulated / emulated, any factors or variables that will be changed during the test, and the measurements used to evaluate the results.

The secondary set of responsibilities covers the following management and signoff issues:

• Provide access to the appropriate sources to elicit and gather the raw detail that will help formulate the Workload Analysis Model
• The review of the Workload Analysis Model for the accuracy and appropriateness of the content and to approve it.

Tailoring

The Workload Analysis Model (contents and format) may require modification to meet the needs of internal or external standards, guidelines, etc.

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