Gartner recently released its 2015 Magic Quadrants for General-Purpose Disk Arrays and another one for Solid-State Arrays. Over the next few weeks we will provide our analysis of these two charts, but first we need to discuss why there are two of them in the first place. The Solid-State Arrays Magic Quadrant is essentially the All-Flash Array Magic Quadrant because none of the vendors listed are delivering any other form of solid-state other than flash. The bigger question is, why even have the separate chart?
All-Flash Arrays Are General-Purpose Arrays
Five years ago when all-flash arrays (AFA) were premium priced solutions purchased to solve a specific performance pain point, separating them from general-purpose disk systems made sense. To cost justify the AFA purchase, the increase in performance had to be directly tied to increasing organizational revenue. In addition to being significantly more expensive, they also lacked features when compared to general-purpose disk systems.
Today, AFAs have similar features to general-purpose arrays and thanks to the decreasing cost of flash as well as technologies like deduplication and compression, they have price points that rival high-performance disk storage. As we discussed in a recent whiteboard video, “Making 3D TLC NAND Ready for the Enterprise“, several AFA vendors are delivering TLC based systems that narrow the price gap even further. The selection of flash no longer needs to be tied to applications whose performance can directly impact revenue. In fact, a case can easily be made for storing all production data on an AFA. That description sounds like a general-purpose array, doesn’t it?
Hard Disks Aren’t Dead Either
Five years ago, general-purpose disk systems, if they used flash at all, used a very small amount of flash to act as a cache. Today, hybrid arrays use very large flash tiers to limit the impact of a cache or tier miss. These hybrid vendors are starting to combine flash with 6TB hard disks. While many are ready to relegate disk to be an archive tier, the reality is that combining hard disks tiers with flash tiers makes for a compelling primary storage solution.
HD Arrays in production remains especially viable as hybrid vendors begin to adopt 8TB and larger Shingled Magnetic Recording (SMR) HDs. For the same bill of materials as a 6TB drive, SMR delivers 8TB of capacity by “shingling” the tracks. Ideally, SMR drives need to be written to sequentially, hybrid arrays with large flash tiers can easily accommodate that requirement.
In other words, hard disks are not dead and each data center will need to examine what approach is best for them; all-flash or hybrid.
One General-Purpose Array Chart Please
Gartner has some unique requirements for an array to qualify into the solid-state chart. If this chart continues to stand on its own, it should be reserved for solid-state arrays that are on the bleeding edge of performance that still focus on revenue generating applications. Most of the products listed on the solid-state chart are from vendors who claim that the arrays listed are acceptable replacements for hard disk based systems. Most of the hard disk arrays on the general-purpose chart today ship with some, and in many cases a lot, of flash storage.
Why this Matters to IT Professionals
This is not a simple matter of overlaying the two charts because Gartner has a different standard for categorizing the products on each chart. A very common engagement for StorageSwiss is helping data centers to decide which general-purpose storage system they should get next. In 2015, every single one of those engagements involved the customer trying to decide between an all-flash system or a hybrid system. Having a single chart would present a clearer picture of how these systems compare. As it stands today, unless the IT planner has their short list down to hybrid only or AFA only, the charts have little value.