WHITE PAPER. Flash in the SAN Panacea or Placebo?

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1 WHITE PAPER Flash in the SAN Panacea or Placebo? 1

2 Storage is at a crossroads. New technologies and architectures are required to ensure optimal performance in virtual data centers without breaking the bank. Enter flash what many people view as the savior to storage I/O bottlenecks. But implementing flash storage can be a bit confusing. Should it go in your storage array? In your servers? Or both? PernixData believes that server flash is the best way to maximize application performance while minimizing storage costs. With FVP software, you get a unique storage architecture that lets you decouple storage performance from capacity for intelligent scale-out growth. Does this obviate the need for flash in the storage array? FVP software actually works with any shared storage device, including hybrid and all flash arrays. But implementing a server side acceleration tier can impact your storage array selection criteria, in some instances minimizing or eliminating the need entirely for flash in your storage device. Re-Think Your Storage Architecture Using a shared storage device has numerous benefits. When information is centralized, it is easy to add capacity, backup and secure stored data. However, a shared storage array gives you a fixed amount of performance (as measured by IOPS). As more VMs are added to your virtualized hosts, the average number of IOPS per host goes down, resulting in poor application performance. The traditional way to get more IOPS is to buy more storage capacity, which is expensive and can result in inefficient over provisioning. Unfortunately, flash arrays do not solve this issue any better than traditional disk arrays. They increase the number of IOPS, but don t introduce a long term solution to the problem. You still have to buy more capacity to get blocks of storage performance. Even if your flash array vendor offers to give you more IOPS every few years if you stay under their maintenance contract, you are still at the mercy of that vendor. You are locked into their hardware, and only get free IOPS in the amount they offer, when they offer them not when you actually need them. In addition, the flash is too far from the applications to solve the latency problem. Lastly, the architecture of a flash array may look innovative now, but will that still be the case in 3 or 4 years? In contrast, FVP software provides a new architecture where storage performance is completely decoupled from capacity. Using inexpensive flash hardware, you can cost effectively add IOPS when you need them, where you need them. This is true scale-out storage performance, enabling predicable growth that keeps pace with your virtual infrastructure (see figure 1). FVP software also gives you complete hardware flexibility. You can mix and match types of flash (e.g. SSD or PCIe from any vendor) across hosts and VMs based on specific performance and cost needs. In addition, as new hardware technologies emerge (e.g. Flash DIMM), they can be easily added. Gone are the days when you are locked into a single piece of hardware for years on end. With FVP software, your storage infrastructure is easily future proofed against obsolete technology. 2

3 IOPS per Host (K) Hosts 4 Hosts 6 Hosts Mid-Range SAN SAN + FVP + Flash Figure 1 Scale-out storage performance with your virtual infrastructure. Getting the Right Performance One of the easiest performance metrics to look at when evaluating storage solutions is IOPS. This is the spec that flows freely off the mouth of every hardware storage vendor, as it is simple to quantify. However, some vendors are disingenuous with their IOPS claims, quoting best case scenarios instead of real world metrics. For example, are the stated IOPS for an all flash array the same when deduplication (or other CPU intensive services) are enabled? Often times they drop by over 50%. With a flash array, you may think you are buying a Ferrari, only to get a Fiat. In contrast, with a decoupled storage architecture each flash device delivers its full IOPS potential. Putting IOPS aside, there is an even more important metric to look at latency. All of the IOPS in the world won t improve application performance if latency is too high. Flash arrays improve latency over traditional storage environments, but they don t offer the same performance as flash in the server. That is because data must traverse the storage fabric and processor before ever reaching the storage media in the array, all of which adds latency. So, even if flash in the storage array increases the speed of reads from and writes to media, other bottlenecks in the storage array still exist. FVP software avoids these bottlenecks by putting flash right where the application resides i.e. inside the host. 3

4 Lower Storage Costs Are you happy with your existing storage array when it comes to capacity, reliability and data services? If so, the last thing you want to do is introduce a completely new product just to get more storage performance. FVP software helps you avoid or delay a storage upgrade by giving you the IOPS you need using your existing storage. In addition, FVP software can offload up to 90% of traffic from your NAS/SAN, extending the life of the storage device by months or years. If buying a new storage array is unavoidable, a new decoupled storage architecture can also help. Because storage performance is handled in the server tier, you can choose a storage array that delivers the most capacity at the best price. The amount of IOPS delivered by the storage array becomes increasingly less relevant, which can save you up to 95% in new hardware investments. See figure 2 for an example of a real world customer evaluation. Cost per IOPS Cost per GB $35.00 $25.00 $32.46 $21.81 $30.00 $20.00 $25.00 $ x Better Value $ x Better Value $15.00 $10.00 $8.42 $10.00 $5.00 $5.00 $2.60 $- $- High-End Mid-Range High-End Mid-Range High-End SAN Mid-Range SAN + SSDs + PernixData FVP Figure 2 A decoupled architecture delivers the best $/IOPS and $/GB. 4

5 Summary PernixData offers the best solution for storage acceleration, including the following unique FVP software advantages: Easy to deploy, with no changes to applications, hosts or storage. Lowest VM latency. True scale-out growth, with unlimited IOPS cost effectively added when and where they are needed. Avoid or delay a storage upgrade by months or years. Lower investments in new storage hardware by up to 95% Perhaps most importantly, FVP software helps you evolve your storage infrastructure, not replace it. PernixData builds a seamless acceleration tier on top of the hardware and software of your choice. You ve spent years developing the right storage tools and procedures for your company we help you evolve this investment for the virtual generation. Copyright 2014 PernixData, Inc. All rights reserved. This product is protected by U.S. and international copyright and intellectual property laws. 5 PernixData is a registered trademark and FVP, Flash Hypervisor, FVP Cluster and Flash Cluster are trademarks of PernixData, Inc. in the United States and/or other jurisdictions. All other brands, products, marks and names mentioned herein may be trademarks or service marks of, and are used to identify, products or services of their respective owners.