Run Schedules Based on a Timer
Schedules based on a timer run the scheduled activity at a certain time or time interval, such as every 2 hours. Use this schedule type when you run the same activity at the same time every day, or when you are indexing, archiving, and purging information from your database.
If the scheduled activity runs one or more times a day regardless of peak and non-peak processing times, use a timer-based schedule instead of a daily schedule.