Intelligent CIO Europe Issue 08 | Page 25

LATEST INTELLIGENCE Some key differences between NetApp and Pure Storage Pure FlashArray//M: FlashArray enables you to scale up and expand capacity by adding storage shelves and SSDs to a pair of storage controllers. However, the maximum capacity is limited by the constraints of each controller’s addressable capacity, a maximum of 10TB to 512TB of flash capacity, depending on the model. Scaling beyond those limits requires a controller swap-out or an investment in additional controller pairs, each of which represents a capacity silo that must be managed separately. In addition, FlashArray storage controllers are deployed in an active/passive configuration in which the active controller processes all I/O requests and the passive controller acts as a passthrough device. If the active controller experiences a failure, all I/O activity fails over to the passive controller. By design, FlashArray systems are limited to 50% utilisation of the maximum processing power available in any controller pair. NetApp AFF: AFF node pairs support active/ active operation so that users can achieve over 50% controller utilisation if needed. Each AFF node pair can scale up to support a maximum of 144 to 480 SSDs, depending on the model, with a maximum physical capacity of 7.3PB for A700 systems. pair are reached, additional FlashArrays must be deployed individually and managed independently. The active/passive controller architecture of the FlashArray can also lead to inefficiencies: with each controller pair operating at half of its maximum performance potential, expensive all-flash storage resources end up underutilised. By contrast, new AFF node pairs can be deployed as part of a cluster architecture and managed as part of a single environment. This provides tremendous flexibility to adapt to changes in workloads over time. For example, when additional processing power is needed, you can non- disruptively add an AFF node pair that is optimised for performance to a cluster. Alternatively, if you need more capacity, you can add high-capacity, all-flash, hybrid, or HDD nodes to the cluster. However, combining Classes and Limits adds complexity and is recommended for ‘more sophisticated users’. NetApp AFF: QoS controls have been available in AFF systems since 2013. They enable the delivery of predictable storage performance for business-critical applications in a shared infrastructure environment. By assigning not-to-exceed performance limits on a per-workload basis, resources can be proactively managed. It is also possible to set minimum performance thresholds for the most business-critical workloads. More recently, an Adaptive QoS feature has been introduced to enable user-defined QoS policies for AFF systems, such as gold, silver and bronze. Adaptive QoS is designed to automatically maintain policy-based performance levels as workloads increase and decrease over time. Comparison: Both AFF and FlashArray enable you to set QoS policies to provide predictable performance levels for different types of workloads, based on business needs. Perhaps the biggest difference between the two is the scope at which these policies can operate. Like other management operations, QoS for a Pure FlashArray must be set up and managed on a per controller-pair basis. AFF QoS operates on a cluster-wide basis and can be used to manage performance across a much larger pool of resources, up to 24 all-flash storage controllers per cluster. The ability to combine policy-based QoS with multiple tiers of storage media (allflash, hybrid and HDD) within a single ONTAP cluster enables IaaS service providers and private cloud administrators to automate storage management and increase operational efficiency. n An AFF cluster can also scale out to support up to 88PB of all-flash capacity. AFF node pairs are available at multiple price/ performance points and can be mixed and matched within a single cluster configuration in many ways – old and new, big and small, all-flash, hybrid flash and all-HDD node pairs – within the same cluster. In addition, the AFF supports the latest in high-capacity SSDs which, at the time of writing, includes 15.3TB SSDs. Comparison: FlashArray offers basic, scale- up capacity expansion by adding storage shelves. When the performance, capacity and host connectivity limits of a controller Download whitepapers free from www.intelligentcio.com/me/whitepapers/ www.intelligentcio.com INTELLIGENTCIO 25