What causes "Unable to invoke 'GetRunnerPath'." in dotnet/BenchmarkDotNet?

Clear the cached prerequisite directory and re-run so InitAsync re-downloads and extracts cleanly.

dotnet/BenchmarkDotNet · error · InvalidOperationException

Unable to invoke 'GetRunnerPath'.

Error message

Unable to invoke 'GetRunnerPath'.

What it means

GetRunnerPath's final guard: GetRunnerPath was found and invoked but returned null (or could not be cast to string). The method exists but did not yield a usable runner path, typically because the prerequisite package never fully extracted its runner binary.

Source

Thrown at src/BenchmarkDotNet.Diagnostics.dotMemory/DotMemoryDiagnoser.cs:65

    protected override string GetRunnerPath()
    {
        var consoleRunnerPackageField = typeof(DotMemory).GetField("ConsoleRunnerPackage", BindingFlags.NonPublic | BindingFlags.Static);
        if (consoleRunnerPackageField == null)
            throw new InvalidOperationException("Field 'ConsoleRunnerPackage' not found.");

        object? consoleRunnerPackage = consoleRunnerPackageField.GetValue(null);
        if (consoleRunnerPackage == null)
            throw new InvalidOperationException("Unable to get value of 'ConsoleRunnerPackage'.");

        var consoleRunnerPackageType = consoleRunnerPackage.GetType();
        var getRunnerPathMethod = consoleRunnerPackageType.GetMethod("GetRunnerPath");
        if (getRunnerPathMethod == null)
            throw new InvalidOperationException("Method 'GetRunnerPath' not found.");

        string? runnerPath = getRunnerPathMethod.Invoke(consoleRunnerPackage, null) as string;
        if (runnerPath == null)
            throw new InvalidOperationException("Unable to invoke 'GetRunnerPath'.");

        return runnerPath;
    }

    internal override bool IsSupported(RuntimeMoniker runtimeMoniker)
    {
        switch (runtimeMoniker)
        {
            case RuntimeMoniker.HostProcess:
            case RuntimeMoniker.Net461:
            case RuntimeMoniker.Net462:
            case RuntimeMoniker.Net47:
            case RuntimeMoniker.Net471:
            case RuntimeMoniker.Net472:
            case RuntimeMoniker.Net48:
            case RuntimeMoniker.Net481:
            case RuntimeMoniker.Net50:
            case RuntimeMoniker.Net60:

View on GitHub (pinned to b515068b61)

Solutions

Clear the cached prerequisite directory and re-run so InitAsync re-downloads and extracts cleanly.
Check disk space and write permissions for the cache directory.
Disable/reconfigure antivirus that may quarantine the JetBrains runner executable.
Match the SelfApi version to your BenchmarkDotNet build.

Defensive patterns

Strategy: fallback

Try / catch

try { /* use dotMemory diagnoser */ }
catch (InvalidOperationException ex) when (ex.Message.Contains("Unable to invoke 'GetRunnerPath'"))
{
    log.Error("dotMemory runner not extracted; check disk/AV/cache and re-run InitAsync.");
}

Prevention

Clear the prerequisite cache so InitAsync re-extracts the runner cleanly.
Ensure disk space and write permissions for the cache directory.
Check antivirus quarantine rules for the JetBrains runner exe.

When it happens

Trigger: InitAsync downloaded the prerequisite but the runner executable was not extracted / not placed where GetRunnerPath expects, so the method returns null. Can also occur if invocation itself throws and the SelfApi catches and returns null internally.

Common situations: Corrupted or interrupted prerequisite download/extraction; antivirus quarantining the runner exe; insufficient disk space or permissions to write the runner; partial state left from a previously failed run.

Related errors

AI-assisted analysis of dotnet/BenchmarkDotNet@b515068b61 (2026-08-13). Data as JSON: /api/errors/09137ba81828cba9. Report an issue: GitHub.