I'm writing a Windows service that runs a variable length activity at intervals (a database scan and update). I need this task to run frequently, but the code to handle isn't safe to run multiple times concurrently.
How can I most simply set up a timer to run the task every 30 seconds while never overlapping executions? (I'm assuming System.Threading.Timer
is the correct timer for this job, but could be mistaken).
You could do it with a Timer, but you would need to have some form of locking on your database scan and update. A simple lock
to synchronize may be enough to prevent multiple runs from occurring.
That being said, it might be better to start a timer AFTER you're operation is complete, and just use it one time, then stop it. Restart it after your next operation. This would give you 30 seconds (or N seconds) between events, with no chance of overlaps, and no locking.
Example :
System.Threading.Timer timer = null;
timer = new System.Threading.Timer((g) =>
{
Console.WriteLine(1); //do whatever
timer.Change(5000, Timeout.Infinite);
}, null, 0, Timeout.Infinite);
Work immediately .....Finish...wait 5 sec....Work immediately .....Finish...wait 5 sec....