Load Testing Error: There is already an active timer with the name '' passed to BeginTimer

Introduction

Without proper setup of a TestContext instance, this error can occur. For a quick overview, you need a full property for the TestContext instance, an you DO NOT need to set the value for it.

Information

If you create a property for TestContext and set the value in the AssemblyInitialize or ClassInitialize you are assigning your property to an instance of TestContext. If you do this in a load test, then every test reuses the same instance of that test context. If you use TestContext.BeginTimer("TimerName"); that instance of the Context adds a new Timer with that name, when the next load test runs it tries to add the same timer to the same TestContext and you get the error listed.

Proper Setup

private TestContext _testContext;

public TestContext TestContext
{
    get { return _testContext; }
    set { _testContext = value; }
}

With this setup, the TestContext property will be set from the TestExecutioner and each load test will get its own TestContext.

Bad Setup

private static TestContext _testContext;

[ClassInitialize]
public static void ClassInitialize(TestContext testContext)
{
    _testContext = testContext;
}

Usage of Timer

TestContext.BeginTimer("DoWorkTimer");
DoWork();
TestContext.EndTimer("DoWorkTimer");

Points of Interest

Timers will show up in the test results under Scenario > Test Case Name > Transactions > Timer Name.

History

• 3^rd November, 2016: Initial version