Software Manual

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• Creating pairs by dataset copying
To create pairs between extents, the same number of resources listed under the column “Number of
resources used per pair” (see Table 47) is necessary, provided that no extents in the same volume
overlap. If the extents used for establishing the pairs overlap, the number of resources required to
establish the relations is the number of resources listed under the column “Number of resources used
per pair” multiplied by the number of extents that overlap.
The following figures illustrate the different cases of copying, for example when the extents overlap or
not. For information about the calculation example of the used resources, see Table 48.
Figure 45 Copying Data in Two Extents that do not Overlap (One T-VOL)
Figure 46 Copying Data in Two Extents that do not Overlap (Two T-VOLs)
Figure 47 Copying Data in Two Extents that do not Overlap (Two S-VOLs)
Figure 48 Copying Data in Three Extents that Overlap (One T-VOL)