How often does a background task run?

Question

Is it possible to find out how often a background task runs for an installed application?

I would like to get an idea about how much work some of my apps are doing in the background.

Answer 1

There are two types of background tasks - Periodic and Resource Intensive, The schedule on which the agent runs depends on which type of task it is. Both types are automatically be un-scheduled after 2 weeks, and the application will have to register it again. Typically an app will do this any time you open it, so if you notice the weather app you use stopped working try opening it again. They are also limited on how many resources (CPU, Memory) they can use.

Periodic Task

A periodic task might do something simple like updating your live tile, and are only allowed to run for 25 seconds. They can run every 20-40 minutes. The exact time depends on how many are scheduled and when they conflict.

When Battery Saver mode is on, these tasks will not run. There is a limit to how many can be scheduled. This is typically around 6, but can vary by device.

Resource Intensive

A resource intensive task can do something that requires a lot of time and bandwidth like syncing data in the cloud (SkyDrive, or something similar). They are allowed to run for up to 10 minutes, and can only run when the device is plugged into an external power source (charging, or plugged into your computer).

They will also only run if the device is connected to wifi. They are not allowed to use your cellular data connection. There are a few other limitations - mainly you can't be using the phone, and it has to be at the lock screen.

You aren't going to be able to tell exactly how much work the background tasks are doing, but the guidelines above will tell you the maximum amount they can do. Be assured that Microsoft took great care in making sure a background task can not use too much of your batter power.

Answer 2

There is not a very clear answer. But according to Microsoft MSDN it will run every 30 minutes.

Periodic agents typically run every 30 minutes. To optimize battery life, periodic agents may be run in alignment with other background processes and therefore the execution time may drift by up to 10 minutes.

Your phone cannot be in the battery safety mode and in 256MB devices they are not supported.

Background Agents Overview for Windows Phone See Constraints for Periodic Agents