HP XP Business Copy makes nearly instantaneous copies of data from XP arrays for development, testing or backup, without ever interrupting your online production. XP Business Copy creates and maintains RAIDprotected copy volumes without interrupting access to the source volumes. Because it makes asynchronous copy volume updates, copies stay up to date with minimal I/O response time degradations for your primary applications. These copy volumes can at any time be “split” from their corresponding source volume and accessed by other applications. So, while copy volumes are being utilized, primary applications can continue to access and update their source volumes as needed, without taking a performance hit. By creating multiple online copies of critical business data without disrupting your business, XP Business Copy lets you get the most from your data. Snapshot XP (XP24000/XP20000/XP12000/XP10000/SVS200 only) is a feature of Business Copy that also replicates data volumes. But it is slightly different in that it makes space-efficient secondary copies that might only be a fraction of the size of the primary copy. Only data that is about to be overwritten in the primary volume is written to the secondary volume. This is called Copy-on-Write. As a result, if the volume capacity required for Snapshot XP can be smaller, then the cost of replication can be lowered. Snapshot is recommended for application environments where the I/O to the secondary volume is not write-centric or intensive (reads or writes). These secondary copies are also known as “virtual volumes”, or V-VOL. All V-VOLs reside in a snapshot pool, or POOL-VOL, which is sized based on the number of V-VOLs and the IO ratio of the primary volumes associated with these V-VOLs.