Parallel Test Execution

This post details the implementation of parallel test execution in Visual Studio, focusing on its availability across IDE, CLI, and VSTS. It explains the core mechanism of launching tests in separate processes, the role of .runsettings files and the MaxCpuCount parameter, and the iterative approach to partitioning tests for parallel execution. It also introduces discoverable ON/OFF toggles in the IDE (Test Explorer) and VSTS (VSTest task) for easier adoption, and clarifies how these settings merge with .runsettings files.