Storage virtualization is most commonly thought of as a way to optimize the use of current storage resources. It brings efficiency to storage operations like provisioning, snapshots, clones (writeable snapshots) and replication. In some cases, like the IBM SAN Volume Controller (SVC), it brings a single data services management capability to a wide variety of storage vendors’ hardware. This ability to provide a single management platform is increasingly important as the silicon storage era begins to hit full stride.

Shared silicon based storage systems are typically available in two forms. The most common is to integrate the technology into a current storage system by using solid state disks (SSD) that have the same form factor as mechanical hard disk drives (HDD). While this is an efficient way to market for the legacy storage manufacturer it’s not the most efficient way to utilize the technology for the data center manager. This implementation model as we have noted in the article "What is a Memory Array?"  wastes space, increases solid state cost and doesn’t provide the full performance benefit possible from silicon based technology.

The other method is the solid state-specific appliance or Memory Array approach found in systems delivered by Violin Memory Systems. This approach breaks the ties to the past HDD form factor and allows for a much denser packaging of flash memory. In this way the Memory Array drives down cost. These systems are also specifically tuned to take advantage of NAND Flash’s unique performance capabilities.

Memory Arrays though lack the mature data management services that are now common in enterprise storage systems, features like provisioning, snapshots and replication. At times they can be a challenge to migrate and integrate into an existing storage infrastructure. These challenges are what makes Violin's announcement of certification with the IBM SVC virtualization platform very significant. The IBM SVC serves as a very effective bridge to solid state for these customers and for organizations looking for ways to transition to “silicon based” storage infrastructures.

With IBM SVC and a Violin Memory Array in place, customers can easily migrate hot, performance sensitive data from their mechanical arrays to silicon based storage. They can also use IBM's Easy Tier capability to automate the analysis and movement of this hot data. We see value in both steps. There are certain sets of data that benefit the most from silicon storage and waiting for a tiering or caching solution to promote that data is unacceptable. These use cases can leverage the migration capability to place data into the “all silicon” tier. In other cases, they can let Easy Tier automate the analysis of data and move it to silicon storage as this move can now be justified.

The two-prong approach allows for applications to be specifically accelerated and have a guaranteed level of performance while efficiently using the remaining silicon storage for Easy Tier functionality. The cost effectiveness, density and reliability of the Violin Memory Arrays make them an ideal product to be that “all silicon” primary storage tier. They have to deliver the performance that the enterprise’s most demanding applications need and they have the capacity, so that Easy Tier functionality can be effective.

Violin has prioritized performance and cost efficient density with their Memory Arrays before they provide data service functions. When combined with an SVC that strategy has paid off. Instead of re-inventing the data services wheel and forcing the user to re-buy that wheel, they can leverage these enterprise proven data services from IBM. Now the Violin Memory Array can deliver thin provisioning, snapshots and replication along with the migration and tiering functionalities mentioned above.

Bringing the efficiency of thin provisioning, snapshots and clones to the Memory Array is ideal. Even with Violin's dense packaging silicon storage is still pricey when compared to mechanical hard disk arrays. Thin provisioning, snapshots and clones allow the storage manager to allocate the appropriate amount of silicon storage (in the right places) to allow their investment to be maximized.

In the silicon environment, with a common data services engine like the SVC, leveraging a mixture of storage platform vendors is critical to reducing cost. For example, SVC would allow the replication of data on a Violin Memory Array to a disaster recovery site. Additionally if performance at the recovery site was not a concern then that replication target could then be moved to more economical mechanical disk arrays.

Finally, with IBM's new Active Cloud Engine the data movement process can be automated. For example, in a desktop virtualization environment data can be pre-positioned to the silicon tier prior to the morning boot/login storm, then migrated down to mechanical storage for the work day. Then, business critical applications can be moved to the silicon tier into the space made available by the demoted desktop virtualization environment. This level of automation brings human intelligence to automated tiering by setting policies for data to be moved based on time of day or certain events. Instead of waiting for a set of data to "warm up" each day, data can be pre-positioned so there is no perceptible performance delay.

A key value of storage virtualization going forward will be its ability to allow storage hardware vendors to design great hardware. In mechanical disk arrays this may be maximizing cost efficiencies and providing the most TBs per rack unit. In silicon storage it’s likely to be maximizing the performance that can be generated per rack unit. The certification with IBM SVC allows Violin to do just that. They can continue to focus on providing a silicon specific Memory Array that leverages the density of Flash memory to deliver the highest performance.

Violin Memory is a client of Storage Switzerland

previous entry: Complete DR for the Mid-market