The setup involves 1200 IP phones with one publisher and three subscribers. The Call Detail Record (CDR) database growth rate is approximately 15 Mb per day.
In order to resolve the issue, set the Log calls with zero duration parameter to false on all the nodes in the cluster.
In case you still run low on disk space, check the application event logs for any error messages. Sometimes the event logs increment when unknown devices try to register to the Cisco CallManager.
For more information refer,