text: For every Remote Copy relationship that is created on an IBM Spectrum Virtualize system, a 
  bitmap table is created to track the copied grains. By default, the system allocates 20 MiB of 
  memory for a minimum of 2 TiB of remote copied source volume capacity. 
  
  Every 1 MiB of memory provides volume capacity for the specified I/O group. So, for 256 KiB 
  grains size, 2 TiB of total Metro Mirror, Global Mirror, or active-active volume capacity is 
  provided. 
  
  See Table 11-14 to calculate the memory requirements and confirm that your system is able 
  to accommodate the total installation size. 
  
  Table 11-14 Memory allocation for FlashCopy services 
  
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              [html]<thead><tr><td>Minimum allocated bitmap space</td><td>Default allocated bitmap space</td><td>Maximum allocated bitmap space</td><td>Minimum functionality when using the default values †</td></tr></thead><tbody><tr><td>0</td><td>20 MiB</td><td>512 MiB</td><td>40 TiB of remote mirroring volume capacity</td></tr></tbody>
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  1Remote copy includes Metro Mirror, Global Mirror, and active-active relationships. 