Is it a good idea to use longtime Thread.Sleep?

Question

I have a job list. Each job has its own run time. They need to run when it comes time. I think two different ways. ``` public class Job { public int JobPeriod {get;set;} // for example as hour: daily = 24, weekly = 7 * 24, monthly = 30 * 24 public DateTime RunTime {get;set} } ``` First Way : I start a new main thread. This thread checks jobs at certain time interval (5 sec, 10 sec etc.). When a job's run time has come, the main thread will start and finish the job. The main thread which continually run in this way. ``` while (true) { lock (Locker) { // checks job list. var jobs = foo.GetIncomingTimeJobs(); foreach (var job in jobs) { ParameterizedThreadStart ts = RunJob; var th = new Thread(ts); th.Start(job); } Thread.Sleep(10000); } } public void RunJob(Job job) { // do somethings } ``` Second Way : When application is started, I create a new thread for each job in the job list. All of these created threads will start. When Job's thread is started, job's thread checks the job's run…

Accepted Answer

Both approaches are in most cases incorrect. Usual solution for this kind of problems is using System.Threading.Timer. Sample code for your case can look like that:

```
private void CheckJobs(object state)
{
    lock (Locker)
    {
        // checks job list.
        var jobs = foo.GetIncomingTimeJobs();
        foreach (var job in jobs)
        {
            var thread = new Thread(foo);
            thread.Start();
        }
    }
}

private void StartProcessing()
{
    var timer = new System.Threading.Timer(CheckJobs, null, 0, 10000);
}
```

When you call StartProcessing() function, the timer will be initialized and jobs list will be checked every 10 seconds.

If you go with Thread.Sleep() your application will become very unresponsive.

Is it a good idea to use longtime Thread.Sleep?

Solution

Problem