text: **Capacity**
  IBM applies the following definitions to capacity: 
  
  (cid:2) Raw capacity 
  
  The reported capacity of the drives in the system before formatting or RAID 
  
  (cid:2) Usable capacity 
  
  The amount of capacity after formatting and RAID available for storing data on a system, 
  pool, array, or MDisk. Usable capacity is the total of used and available capacity. For 
  example, 50 TiB used, 50 TiB available is a usable capacity of 100 TiB. 
  
  (cid:2) Used capacity 
  
  The amount of usable capacity taken up by data in a system, pool, array, or MDisk after 
  data reduction techniques were applied. 
  
  (cid:2) Available capacity 
  
  The amount of usable capacity that is not yet used in a system, pool, array, or MDisk. 
  
  (cid:2) Effective capacity 
  
  The amount of provisioned capacity that can be created in the system or pool without 
  running out of usable capacity given the current data reduction savings being achieved. 
  This capacity equals the physical capacity divided by the data reduction savings 
  percentage. 
  
  (cid:2) Provisioned capacity 
  
  Total capacity of all volumes in a pool or system. 
  
  (cid:2) Written capacity 
  
  The amount of usable capacity that would be used to store written data in a pool or system 
  before data reduction is applied. 