MetalamaConceptual documentationConfiguring and troubleshootingCapturing performance data
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Capturing performance data

If you are experiencing performance issues with Metalama, our support team might request to profile the Metalama or IDE processes.


Profiling snapshots may contain potentially confidential information

Profiling snapshots can include call stacks from your compile-time code. While we treat process dumps as confidential material, your company might not permit you to send us a profiling snapshot without management approval.


Metalama uses JetBrains dotTrace to create performance snapshots. dotTrace will be automatically downloaded upon first use. You do not need a license to collect performance, but you may need to acquire a license if you want to analyze this data.

Step 1. Install the PostSharp Command-Line Tool

Install the metalama command-line tool following the instructions in Installing the Metalama Command Line Tool.

Step 2. Edit diagnostics.json

Run the command:

metalama config edit diagnostics

This command should open a diagnostics.json file in your default editor.

The profiling/processes section lists processes that need to be profiled. The values are false by default, and you can set them to true for the processes you want to profile:

  • Compiler: the compile-time process.
  • Rider: the design-time Roslyn process running under Rider.
  • DevEnv: the UI process of Visual Studio (note that there is no aspect code running in this process).
  • RoslynCodeAnalysisService: the design-time Roslyn process running under Visual Studio (this is where the aspect code runs).

In the example below, Metalama is set up to profile the compiler process.

 // ...
"profiling": {
    "processes": {
     "DotNetTool": false,
      "BackstageWorker": false,
      "OmniSharp": false,
      "Compiler": true,
      "TestHost": false,
      "CodeLensService": false,
      "Other": false,
      "ResharperTestRunner": false,
      "DevEnv": false,
      "Rider": false,
      "RoslynCodeAnalysisService": false

Step 3. Execute Metalama

Restart the profiled processes:

  • If you enabled profiled for the Compiler process, restart the Roslyn compiler processes using metalama kill.
  • If you enabled profiled for any design-time processes, restart your IDE.

Perform the actions that cause the issue.


Remember to disable the diagnostic setting once you have finished.

Step 4. Stop the profiled processes

Close your IDE. If you are profiling the compiler processes, run metalama kill.

Wait a file with extension *.dtp is created under the %TEMP%\Metalama\Profiling directory.

Step 5. Upload the snapshots to an online drive

You will find the profiling snapshots in the %TEMP%\Metalama\Profiling directory. Zip the whole directory and upload this file to an online storage service like OneDrive.

Step 6. Send us the URL through a private channel


NEVER share the snapshot URL publicly on a service like GitHub Issues.

Instead, kindly send us the link via email or private message on Slack.