36 Implementing the IBM Storwize V7000 with IBM Spectrum Virtualize V8.2.1
2.5.21  Data Reduction Pools
Data Reduction Pools (DRP) represent a significant enhancement to the storage pool 
concept. The reason is the virtualization layer is primarily a simple layer that runs the task of 
lookups between virtual and physical extents. 
Data Reduction Pools is a new type of storage pool and implements techniques, such as 
thin-provisioning, compression, and deduplication to reduce the amount of physical capacity 
that is required to store data, and decrease the network infrastructure required. Savings in 
storage capacity requirements translate into reduction in the cost of storing the data.
The storage pools enable you to automatically de-allocate and reclaim capacity of 
thin-provisioned volumes that contain deleted data and for the first time, enable this reclaimed 
capacity to be reused by other volumes. Data reduction provides more performance from 
compressed volumes because of the new log structured pool that is implemented.
2.5.22  Deduplication
Data deduplication is one of the methods of reducing storage needs by eliminating redundant 
copies of a file. Data reduction is a way to decrease the storage disk and network 
infrastructure that is required, and optimize use of storage disks and improve data recovery 
infrastructure efficiency. Existing data or new data are standardized into chunks that are 
examined for redundancy. If data duplicates are detected, pointers are shifted to reference a 
single copy of the chunk and the extra duplicate data is then released.
Deduplication has benefits, such as storing more data per physical storage system, which 
saves energy by using fewer disk drives and decreasing the amount of data that must be sent 
across a network to another storage for backup replication and disaster recovery.
2.5.23  IP replication
IP replication was introduced in V7.2 and allows data replication between IBM Spectrum 
Virtualize family members. IP replication uses IP-based ports of the cluster node canisters. 
This function is transparent to servers and applications in the same way that traditional 
FC-based mirroring is. All remote mirroring modes (Metro Mirror, Global Mirror, and Global 
Mirror with changed volumes) are supported.
The configuration of the system is straightforward, and IBM Storwize family systems normally 
find each other in the network and can be selected from the GUI.
IP replication includes Bridgeworks SANSlide network optimization technology and is 
available at no extra charge. Remember, remote mirror is a chargeable option, but the price 
does not change with IP replication. Remote mirror users have access to the function at no 
extra charge.
IP connections that are used for replication can have long latency (the time to transmit a 
signal from one end to the other). This latency can be caused by distance or by many “hops” 
between switches and other appliances in the network. Traditional replication solutions 
transmit data, wait for a response, and then transmit more data, which can result in network 
utilization as low as 20% (based on IBM measurements).