Architecting a vCloud Availability for vCloud Director Solution : vCloud Director Configuration : 5.5 Storage Management : 5.5.3 Storage Management Recommendations
   
5.5.3 Storage Management Recommendations
Dedicate datastores or storage policies to Org VDCs used for replication.
Use conservative datastore thresholds in vCloud Director (keep red threshold to 33%-50% of total datastore size).
Charge tenants for cold and hot disk data.