Timer Behavior

Timer can behave differently depending on the scenario at with they are started. Some of the scenarios and Timer behavior is as described below.

• For a repeating timer, if a timed transaction continues past the point at which the next tick is due, then that tick is discarded and the next due tick will be used.

  For example:

  A timer is configured to tick every 20 seconds. So this means that the timer will normally tick at the following times:

  20, 40, 60, 80, 100, etc

  Now let's say that on the second tick, the timed transaction took 25 seconds to complete. This means that the transaction which started at the 40 second mark completed at the 65 second mark, and is therefore deemed to have 'missed' the 60 second mark. So the next time the timer will tick will be at the 80 second mark. So the actual times the timer will have ticked are:

  20, 40, 80, 100

• When a timer is specified with an initial duration, that duration is relative to the time at which the timer was created. It is not relative to the time at which the transaction was committed - even though the timer cannot actually begin ticking until the transaction in which it was created has been committed.

  For example, the user invokes a rather long online transaction which does the following:

  • Creates Timer A with an initial duration of 60 seconds.
  • Does some processing which takes 20 seconds.
  • Creates timer B with an initial duration of 60 seconds.
  • Commits the transaction.

  Next the following will happen:

  • 60 seconds after it was created, Timer A will start ticking.
  • 20 seconds later, Timer B will start ticking.

  i.e. even though these timers were committed at the same time, each retains its own individual start time.