For 20 years or more, conventional storage has been confined to physical workloads, in the form of block level storage and file storage which both support enterprise applications.
Block level storage is a type of platform that was made up of vendors selling big storage boxes that could save the manageable amount of data a company held. File storage helped companies to save and order the large amounts of data that was created by the digital transformation. The storage world was simple and could easily be apportioned into SAN, NAS and DAS markets in different capacities, depending on the use case.
Then virtualization arrived, taking storage away from physical workloads, transforming the IT industry and bringing a number of challenges for legacy storage solutions. Now, along with SAN, NAS and DAS, storage has another term, VAS (VM-aware storage).
The history of data storage reaches back for decades. The reality is there were large enterprise storage solutions for mainframes long before the PC-era kickstarted an explosion in storage. While the initial focus was on direct attached storage to PCs and servers (DAS), organisations increasingly looked over time to the network to deliver storage resources across their operations using NAS or SAN.
Conventional storage, whether direct attached or networked, has defined storage for decades – and would probably continue to have done for years if not for two unforeseen developments that changed everything: virtualization and the rise of cloud technology.
The shift away from physical workloads
Today about 75 percent of all workloads in modern day data centres are virtualized and this number is only expected to grow. Legacy storage technologies like DAS, NAS and SAN are ill-equipped to support virtualization because they were designed for a physical world, decades before virtualization even existed.
The two biggest storage bottlenecks when it comes to storing data are performance and management complexity. The biggest concerns for virtualization and storage admins alike are application performance and random I/Os. Virtual environments generate far more rando m I/O patterns than physical ones and can seriously choke storage because servers can support upwards of thousands of virtual servers, each generating its own I/O stream, but conventional storage can’t keep up.
To overcome the technological limitations of conventional storage solutions, vendors have used the benefits of flash to quench the thirst for higher IOs. Flash can achieve up to 20 times lower latencies and tens of thousands of IOPs, while offering high density and low power consumption. While rather expensive in the beginning, the declining price of flash has helped storage vendors with struggling conventional physical storage systems to stick an expensive band-aid on their products to bypass the storage bottleneck. Adding a flash layer seemingly solved the performance issues customers were facing due to the increased workloads and demand of virtualization and cloud computing.
The advent of VM-aware storage (VAS)
But while they are faster, legacy storage systems with added flash still have a fundamental limitation, their approach is still conventional -LUN and volume based.
Flash storage puts a lot of IOPS at an organisation’s disposal, but it needs to know where to put the flash to work. This is essential if a company’s virtualization footprint is expanding so that it can grow as efficiently as possible. And it requires that a storage admin be able to see performance and behaviour for individual VMs. Companies need to be able to see at the VM level to resolve the data centre disconnect.
When real-time analytics can lay bare the needs of individual VMs, they can also be effectively balanced across all-flash and hybrid-flash devices, for an even more efficient use of resources. Companies that start to think less in conventional storage terms (LUNs, volumes, striping, etc.) and more in VMs, will better contain costs and amplify value. After all, storage doesn’t drive business value, applications do. And only VM-aware storage can take the focus off storage itself and direct it at the applications that matter.
Kieran Harty is chief technology office and co-founder of Tintri.