Here, you will find a .NET Core project used as a study case to evaluate the different performances of using IClassFixture in your xUnit projects. The comparison was also between an in-memory database and a real database. Check out the results in English here, or in Portuguese here.
The results were collected by executing the tests through the command line with verbosity normal and logging them as a TRX file in a versioned folder.
dotnet test --verbosity n --logger:"trx;LogFileName=v{version}\{file-name}.trx"