Profile Running Process
To profile an already running process
Run dotTrace as a standalone application. The dotTrace Home window will open.
In the left panel, select Attach to Running App.
In the middle panel, select the .NET process you are going to profile. Only processes running on .NET Framework 4.0 or higher are displayed and available to attach.
In the right panel, in Profiler Options, specify profiling type. When attaching the profiler to a process, you can choose only between Sampling (evaluate performance and determine slowest methods in your app) and Timeline (determine slowest methods and how method calls are distributed in time).
For more details on profiler options, refer to the Profiler Options section.
Optionally, if you are going to control profiling session (take snapshots, end session, and so on) using the API (rather than the Controller window), select Advanced and Use profiler API. For more details on how to control profiling using the API, refer to the Control Profiling Session with API chapter.
Collect profiling data (snapshots). For more details on how to control profiling session, refer to Control Profiling Session (if you control the session manually) or to Control Profiling Session with API (if you control profiling using the API).
After you collect the data, detach the profiler from the process using the Detach button of the Controller window. If you use the API to control profiling, detaching must be provided by your code.