Abstract: A virtual data storage system includes a device emulator and a storage system. The virtual data storage system requires the performance of activities on a scheduled basis. An activity scheduler manages a set of pending, running, and completed activities. The activity scheduler provides scheduler services for use by external processes. A scheduler process examines a list of to-be-run activities. For each activity that has reached its scheduled time, that activity is considered for starting. An activity monitor process monitors started activities. Upon determining a problem with an activity, a recovery process is performed. The recovery process includes returning the problem activity to the list of to-be-run activities.