Best way to run scheduled tasks

Question

Today we have built a console application for running the scheduled tasks for our ASP NET website  But I think this approach is a bit error prone and difficult to maintain  How do you execute your scheduled task  in an windows IIS ASP NET environment   Update    Examples of tasks    Sending email from an email-queue in the database Removing outdated objects from the database Retrieving stats from Google AdWords and fill a table in the database

User · Answer

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

User · Answer

This technique by Jeff Atwood for Stackoverflow is the simplest method I ve come across  It relies on the  quot cache item removed quot  callback mechanism build into ASP NET s cache system Update  Stackoverflow has outgrown this method  It only works while the website is running but it s a very simple technique that is useful for many people  Also check out Quartz NET

User · Answer

A New Task Scheduler Class Library for  NET   Note  Since this library was created  Microsoft has introduced a new task scheduler  Task Scheduler 2 0  for Windows Vista  This library is a wrapper for the Task Scheduler 1 0 interface  which is still available in Vista and is compatible with Windows XP  Windows Server 2003 and Windows 2000   http   www codeproject com KB cs tsnewlib aspx

User · Answer

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

User · Answer

Use Windows Scheduler to run a web page   To prevent malicous user or search engine spiders to run it  when you setup the scheduled task  simply call the web page with a querystring  ie   mypage aspx from scheduledtask  Then in the page load  simply use a condition       if  Request Querystring  from       scheduledtask               executetask        This way no search engine spider or malicious user will be able to execute your scheduled task

User · Answer

I ve used Abidar successfully in an ASP NET project  here s some background information    The only problem with this method is that the tasks won t run if the ASP NET web application is unloaded from memory  ie  due to low usage    One thing I tried is creating a task to hit the web application every 5 minutes  keeping it alive  but this didn t seem to work reliably  so now I m using the Windows scheduler and basic console application to do this instead   The ideal solution is creating a Windows service  though this might not be possible  ie  if you re using a shared hosting environment    It also makes things a little easier from a maintenance perspective to keep things within the web application

User · Answer

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

User · Answer

This library works like a charm http   www codeproject com KB cs tsnewlib aspx  It allows you to manage Windows scheduled tasks directly through your  NET code

User · Answer

Why reinvent the wheel  use the Threading and the Timer class       protected void Application Start                 Thread thread   new Thread new ThreadStart ThreadFunc            thread IsBackground   true          thread Name    ThreadFunc           thread Start               protected void ThreadFunc                 System Timers Timer t   new System Timers Timer            t Elapsed    new System Timers ElapsedEventHandler TimerWorker           t Interval   10000          t Enabled   true          t AutoReset   true          t Start               protected void TimerWorker object sender  System Timers ElapsedEventArgs e                  work args

User · Answer

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

User · Answer

You can easily create a Windows Service that runs code on interval using the  ThreadPool RegisterWaitForSingleObject  method  It is really slick and quite easy to get set up  This method is a more streamlined approach then to use any of the Timers in the Framework   Have a look at the link below for more information   Running a Periodic Process in  NET using a Windows Service  http   allen-conway-dotnet blogspot com 2009 12 running-periodic-process-in-net-using html

User · Answer

I ve found this to be easy for all involved    Create a webservice method such as DoSuchAndSuchProcess Create a console app that calls this webmethod  Schedule the console app in the task scheduler     Using this methodology all of the business logic is contained in your web app  but you have the reliability of the windows task manager  or any other commercial task manager to kick it off and record any return information such as an execution report  Using a web service instead of posting to a page has a bit of an advantage because it s easier to get return data from a webservice

User · Answer

Create a custom Windows Service   I had some mission-critical tasks set up as scheduled console apps and found them difficult to maintain  I created a Windows Service with a  heartbeat  that would check a schedule in my DB every couple of minutes  It s worked out really well   Having said that  I still use scheduled console apps for most of my non-critical maintenance tasks  If it ain t broke  don t fix it

User · Answer

All of my tasks  which need to be scheduled  for a website are kept within the website and called from a special page   I then wrote a simple Windows service which calls this page every so often   Once the page runs it returns a value   If I know there is more work to be done  I run the page again  right away  otherwise I run it in a little while   This has worked really well for me and keeps all my task logic with the web code   Before writing the simple Windows service  I used Windows scheduler to call the page every x minutes      Another convenient way to run this is to use a monitoring service like Pingdom   Point their http check to the page which runs your service code   Have the page return results which then can be used to trigger Pingdom to send alert messages when something isn t right

User · Answer

One option would be to set up a windows service and get that to call your scheduled task   In winforms I ve used Timers put don t think this would work well in ASP NET

User · Answer

If you own the server you should use the windows task scheduler  Use AT    from the command line to see the options    Otherwise  from a web based environment  you might have to do something nasty like set up a different machine to make requests to a certain page on a timed interval

[asp.net] Best way to run scheduled tasks

Examples related to asp.net

Examples related to windows

Examples related to iis

Examples related to scheduled-tasks