Sample program behavior not what's expected and makes no sense

question
1

I’ve written a small test application to get a feel for Hangfire. But the results are not at all what I was expecting.

Here’s the code.

GlobalConfiguration.Configuration
    .UseMemoryStorage();

using var server = new BackgroundJobServer();
TaskExecutor tasks = new();

Console.WriteLine("Hangfire Server started. Press any key to exit...");
Console.WriteLine($"Start: {tasks.StartTime:g}");

RecurringJob.AddOrUpdate("1", () => tasks.RunTask(1), "*/1 * * * *");
RecurringJob.AddOrUpdate("2", () => tasks.RunTask(2), "*/2 * * * *");
RecurringJob.AddOrUpdate("3", () => tasks.RunTask(3), "*/3 * * * *");
RecurringJob.AddOrUpdate("4", () => tasks.RunTask(4), "*/4 * * * *");
RecurringJob.AddOrUpdate("5", () => tasks.RunTask(5), "*/5 * * * *");

Console.ReadKey();

class TaskExecutor
{
    public DateTime StartTime { get; private set; }

    public TaskExecutor()
    {
        StartTime = DateTime.Now;
    }

    [DisableConcurrentExecution(30 * 60)]
    public void RunTask(int interval)
    {
        Console.WriteLine($"{interval} : Start {Math.Round((DateTime.Now - StartTime).TotalMinutes):#,0.##} minutes");
        Thread.Sleep(2000);
        Console.WriteLine($"{interval} : End");
    }
}

Here’s the output I’m expecting.

1 : Start 1 minutes
1 : End
1 : Start 2 minutes
1 : End
2 : Start 2 minutes
2 : End
1 : Start 3 minutes
1 : End
3 : Start 3 minutes
3 : End
1 : Start 4 minutes
1 : End
2 : Start 4 minutes
2 : End
4 : Start 4 minutes
4 : End
1 : Start 5 minutes
1 : End
5 : Start 5 minutes
5 : End

Instead, here’s the actual output.

1 : Start 0 minutes
1 : End
3 : Start 0 minutes
3 : End
2 : Start 0 minutes
2 : End
1 : Start 0 minutes
1 : End
5 : Start 0 minutes
5 : End
1 : Start 0 minutes
1 : End
4 : Start 0 minutes
4 : End
3 : Start 0 minutes
3 : End
2 : Start 0 minutes
2 : End
1 : Start 0 minutes
1 : End

The order and timing make no sense to me. And my number of minutes elapsed remains at zero. Debugging the code, it appears the reason the elapsed time doesn’t change is because my TaskExecutor is being recreated. This too is completely unexpected. Why would there be more than one instance of this class?

Can anyone help me make sense of this?

2

This goes to your other post. It is creating a new instance of TaskExecutor for each job which means StartTime is always the current time.