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Dummy Activities

Sometimes it is useful for an Activity to control the flow of work between two Queues without actually holding the work for any time in the Activity. This is called a Zero Time or Dummy Activity as the step does not actually exist in the process. This is achieved by setting the Activity to take zero time by using a Fixed Distribution.

However there can be issues with this approach:

  1. If the destination object of the Activity has no capacity limit then all the work in the source object will pass to the destination object immediately after it enters the source object.
  2. If the destination object has a capacity limit then 1 item of work will leave the source object before the destination object can accept it, and will wait in the Activity.

Two options avoid the above situations: Wait till exit clear and Zero timing.