Friday, December 9, 2011

5 minutes, 60 seconds, and ATS: the Friday learning

It is Friday afternoon and a slow day, time to look up an interesting topic in the DB2 Information Center: ATS.
  • What is ATS? It is the Administrative Task Scheduler.
  • It enables DB2 to automate the execution of tasks.
  • 5 minutes? Every 5 minutes ATS checks for new or updated tasks and executes them if needed.
  • 60 seconds? If the ATS daemon fails to execute a task, it will retry the execution every 60 seconds.
  • Don't overload! If a specific task is still running, ATS won't start another instance of the same task.
  • ADMIN_TASK_STATUS is an administrative view to retrieve status information.
  • SYSTOOLSPACE is the place where task data is stored. It is a user data tablespace.
  • And, last but not least, what is a task...? Tasks need to be encapsulated in user-defined or system-defined procedures. ADMIN_CMD is such a system-defined procedure which can be used to backup a database, run reorg, collect statistics via runstats, etc.
So much as introduction, you can read more details at the linked pages.