Edit think times to simulate website human interaction delays in load tests scenarios
Applies to: 
Visual Studio 
Visual Studio for Mac
Note
This article applies to Visual Studio 2017. If you're looking for the latest Visual Studio documentation, see Visual Studio documentation. We recommend upgrading to the latest version of Visual Studio. Download it here
Think times are used to simulate human behavior that causes people to wait between interactions with a website. Think times occur between requests in a web performance test and between test iterations in a load test scenario. Using think times in a load test can be useful in creating more accurate load simulations. You can change whether think times are used or ignored in load tests. You change whether think times are used in your load tests in the Load Test Editor.
The think profile is a setting that applies to a scenario in a load test. The setting determines whether the think times that are saved in the individual web performance tests are used during the load test. If you want to use think times in some web performance tests but not in others, you must place them in different scenarios. For more information about scenarios, see Edit load test scenarios.
Initially, you set whether you use think times in your load tests when you create the load test using the New Load Test Wizard. For more information, see Edit load test scenarios.
The Think Profile options are described in the following list:
Note
Web performance and load test functionality is deprecated. Visual Studio 2019 is the last version where web performance and load testing will be fully available. For more information, see the Cloud-based load testing service end of life blog post. To reduce the impact on users some minimum support is still available in Visual Studio 2022 Preview 3 or later. Users should also note web performance and load test functionality only supports Internet Explorer which is not available on Windows 11 and some versions of Windows 10. Read more on Internet Explorer Lifecycle policy.
Off
Think times are ignored. Use this setting when you want to generate maximum load to heavily stress your web server. Do not use it when you are trying to create more realistic user interactions with a web server.
On
Think times are used exactly as they were recorded in the web performance test. Simulates multiple users running the web performance tests exactly as recorded. Because a load test simulates multiple users, using the same think time could create an unnatural load pattern of synchronized virtual users.
Normal Distribution
Think times are used, but varied on a normal curve. Provides a more realistic simulation of virtual users by slightly varying the think time between requests.
Note
For a complete list of the load test scenario properties and their descriptions, see Load test scenario properties.
Change the think profile
To change a think profile in a load test scenario
From the web performance and load test project, open a load test.
In the Load Test Editor, choose the scenario node where you want to change the Think Profile. The Think Profile is displayed in the Properties window. Press F4 to display the Properties window.
Change the Think Profile property in the Properties window.
After you have finished changing the properties, choose Save on the File menu. You can then run your load test with the new think profile.