When differential data is being copied, longer copying time can be expected for the following program products:

• ShadowImage
• Volume Migration

The following table shows the amount of additional copy time expected for the affected program products. The increase in copy time may be as much as doubled and depends on the number of pairs set to the program product.

Capacity of Migrated Volume (MB)	Estimated delay in copying speed (in minutes)
0 - 1,000	4
1,001 - 5,000	18
5,001 - 10,000	37
10,001 - 50,000	186
50,001 - 100,000	372
100,001 - 500,000	1,860
500,001 - 1,000,000	3,720
1,000,001 - 2,150,400	9,667

The above estimates are calculated based on the assumption that the workload for update I/Os for the migrated volume is 50 IOPS for one volume.