text: You can adjust the cycling period by using the**chrcrelationship -cycleperiodseconds**
  **<*60 - 86400*>**command from the CLI. The default value is 300 seconds. If a copy does not 
  complete in the cycle period, the next cycle does not start until the prior cycle completes. For 
  this reason, the use of Change Volumes gives you the following possibilities for RPO: 
  
  (cid:2) If your replication completes in the cycling period, your RPO is twice the cycling period. 
  
  (cid:2) If your replication does not complete within the cycling period, RPO is twice the completion 
  time. The next cycling period starts immediately after the prior cycling period is finished. 
  
  Carefully consider your business requirements versus the performance of Global Mirror with 
  Change Volumes. Global Mirror with Change Volumes increases the intercluster traffic for 
  more frequent cycling periods. Therefore, selecting the shortest cycle periods possible is not 
  always the answer. In most cases, the default must meet requirements and perform well. 
  
  **Important:**When you create your Global Mirror Volumes with Change Volumes, make 
  sure that you remember to select the change volume on the auxiliary (target) site. Failure 
  to do so leaves you exposed during a resynchronization operation. 