All-flash arrays are known for IOPS and low latency. But there is another feature of flash that may end up being even more important than performance; density. All-flash array vendors are beginning to deliver PBs of capacity in a few rack units, far less than an equivalent hard disk-based system. Even though the all-flash array may be more expensive per TB, the savings per rack unit makes up for it. As a result, IT professionals have a new decision to make. Instead of deciding whether they should buy an all-flash array, the question should be whether they should by a high performance all-flash array or buy a high density all-flash array?
What is a High Density All-Flash Array?
A high density all-flash array uses high capacity flash modules tightly packed into a storage system. Again, PBs in a few rack units is not unheard of. Tightly packing a bunch of capacity into a single storage cabinet isn’t a problem with flash modules like it is with hard disk drives, because a flash does not create vibration nor the amount of heat that hard drives do. While there is a potential performance degradation in this configuration as compared to a more traditional flash array, for most environments these systems will more than meet the requirements.
Which All-Flash Array is Right for You?
Now that IT has two all-flash array types to choose from, deciding which one is right for your organization is critical. While the high capacity all-flash array may be less expensive per GB, you do need to have enough capacity to justify the initial investment. If your capacity needs are not going to reach that PB class requirement anytime soon then one of the high density systems is not a good first step for you.
Also, as stated above, there is a performance impact in using these high density systems. The flash modules themselves may be slower but the bigger impact is that the inter-connectivity is essentially oversubscribed.
Despite these potential downsides of high-capacity systems, if you can justify the capacity investment and the organization’s performance demands are “normal” then one of the these systems is very compelling. And there will be many organizations that will need both a high performance all-flash array and a highly dense all-flash array.
Sorting through all these options to help you determine which type of all-flash array is best for your organization is the goal of our on demand webinar “The Bifurcation of the Flash Market“.