ibm storage

Understanding IBM External Storage Data Reduction Technology

There are a few high-valued benefits external storage can serve up to the IBM i infrastructure stack.  The one we are going to focus on today is something IBM calls “Data Reduction”.  Data reduction technology is known in the IBM Storage world as DRP or Data Reduction Pools and is the backbone for delivering three high-value tools for reducing your overall storage footprint on disk.  That means you have to buy less physical storage to support your workload, saving you some real cash money.

Let’s look at the three pieces of tech that are available with DRP to optimize your storage on disk.

  • Thin Provisioning – Allows you to define a certain amount of storage to an individual IBM i partition but only allocate the actual storage at the SAN as the partition needs it. For example, you have an IBM i partition that you want to allocate 4TB of storage to, which will be 60% utilized.  Instead of allocating all 4TB to that partition, thin provisioning tricks IBM i into thinking it has a full 4TB of storage but the SAN only physically allocates 2.4TB-ish of storage and allocates additional storage as needed.  This is highly valuable when you have many partitions.  If you had 10x of these partitions. Instead of needing 40TB+ of storage you would need 24TB’s plus, say another 10TB’s for growth.  That is a pretty big reduction in physical storage.
  • Compression – If you are in this industry and don’t know what compression is from a high level, Google it. IBM Spectrum Virtualize allows you to turn on compression, which compresses and decompresses data as it gets written/read.
  • Deduplication – reduces the overall footprint by taking duplicate blocks of data and removing them. This is great tech but due to the nature of IBM i and it mostly being used for database type workloads, this does not provide a ton of value for IBM i workloads.

DRP technology enables you to create five types of volumes for supporting your workloads.

  • Fully allocated – This type provides no storage efficiency, but the best performance, and is available for migration.
  • Thin – This type provides storage efficiency, but no compression or deduplication.
  • Thin and Compressed – This type provides storage efficiency with compression, and this combination provides the best performance numbers.
  • Thin and Deduplication – This type provides storage efficiency, but without compression.
  • Thin, Compressed, and Deduplication