Best way to run scheduled tasks [closed]

Answer 1

Additionally, if your application uses SQL SERVER you can use the SQL Agent to schedule your tasks. This is where we commonly put re-occurring code that is data driven (email reminders, scheduled maintenance, purges, etc...). A great feature that is built in with the SQL Agent is failure notification options, which can alert you if a critical task fails.

Answer 2

Here's another way:

1) Create a "heartbeat" web script that is responsible for launching the tasks if they are DUE or overdue to be launched.

2) Create a scheduled process somewhere (preferrably on the same web server) that hits the webscript and forces it to run at a regular interval. (e.g. windows schedule task that quietly launches the heatbeat script using IE or whathaveyou)

The fact that the task code is contained within a web script is purely for the sake of keeping the code within the web application code-base (the assumption is that both are dependent on each other), which would be easier for web developers to manage.

The alternate approach is to create an executable server script / program that does all the schedule work itself and run the executable itself as a scheduled task. This can allow for fundamental decoupling between the web application and the scheduled task. Hence if you need your scheduled tasks to run even in the even that the web app / database might be down or inaccessible, you should go with this approach.

Answer 3

We use console applications also. If you use logging tools like Log4net you can properly monitor their execution. Also, I'm not sure how they are more difficult to maintain than a web page, given you may be sharing some of the same code libraries between the two if it is designed properly.

If you are against having those tasks run on a timed basis, you could have a web page in your administrative section of your website that acts as a queue. User puts in a request to run the task, it in turn inserts a blank datestamp record on MyProcessQueue table and your scheduled task is checking every X minutes for a new record in MyProcessQueue. That way, it only runs when the customer wants it to run.

Hope those suggestions help.

Answer 4

I'm not sure what kind of scheduled tasks you mean. If you mean stuff like "every hour, refresh foo.xml" type tasks, then use the Windows Scheduled Tasks system. (The "at" command, or via the controller.) Have it either run a console app or request a special page that kicks off the process.

Edit: I should add, this is an OK way to get your IIS app running at scheduled points too. So suppose you want to check your DB every 30 minutes and email reminders to users about some data, you can use scheduled tasks to request this page and hence get IIS processing things.

If your needs are more complex, you might consider creating a Windows Service and having it run a loop to do whatever processing you need. This also has the benefit of separating out the code for scaling or management purposes. On the downside, you need to deal with Windows services.