Neil Salamack

Commodity SSD or Purpose Built Flash?  What You Need to Know

Blog Post created by Neil Salamack Employee on Dec 15, 2016

There’s a lot of hype surrounding the journey to an all-flash data-center and much of this has been fueled by vendors driving their flash solutions as the “cure-all” for any and all workloads.  While the improvement in application response and processing is what makes the move to flash a no-brainer, there are a few things that you should consider based on the fact that “All flash products are not created equally”.



This brings to mind a trip I made to Los Angeles last year. While on Sunset Boulevard I spotted a wrecked Lamborghini while on a morning walk. I commented to the attendant, “Wow someone lost a lot of money”.  The attendant was quick to point out that the car was a birthday gift for a 19 year old. He had the car only one month before totaling it after losing control and hitting a fire hydrant during an impromptu street race.  Luckily he was not injured with the exception of his pride and his dad’s wallet. The lesson in this case is that even with state of the art technology, speed without control can result in a very costly mistake.  Similarly, speed without high availability can also be costly when comparing flash solutions.  The difference is that downtime can not only cost a business millions of dollars in lost productivity and revenue, it could cost you a career. This is why I would like to slice through the flash hype and discuss what you should consider before choosing a flash vendor or solution.


What are Your Use Cases, and what is the Priority for the Line of Business?
It’s great to have choices in flash and there are cases where commodity SSD’s (solid state drives) deliver “good enough” performance at low cost. However your selection process should really be driven by the business outcomes that you are trying to achieve. For example, if your goal is to deliver low latency and improve the user experience of a web server, then commodity flash may be good enough. However just as all flash is not created equal, neither are your applications.  In many cases you will be using all-flash arrays to modernize infrastructure that is currently running mission critical applications. With applications like Oracle, SAP, SQL and other highly virtualized applications, the expectation is non-stop service as downtime could be catastrophic and extremely costly for the business. Purpose-built flash is optimized for enterprise availability and it’s no wonder why it is often selected over SSD’s as an underpinning for mission critical processes that have moved to flash from 15K rotating disk.  In fact, Gartner has claimed in the 2016 report, “Critical Capabilities for Solid State Arrays”, that “Although most vendors have embraced the use of standard hardware and solid-state drives to increase density and performance, an increasing number of vendors continue to develop their own specialized SSD modules”. The reason for this is clear, customers need more from enterprise flash as they make decisions towards an All-Flash Datacenter.  Availability has become the top selection criteria for flash arrays in the enterprise and the fact that purpose built flash provides better performance than commodity SSD’s is icing on the cake.


What are the Differences between Commodity SSD’s and Proprietary Flash Modules?
All-flash arrays may employ commodity SSD’s (Solid State Disk), or proprietary modules which have been purpose built for flash.  With all of the hype surrounding “commodity” and open-source solutions, it’s easy to assume that flash solutions based on low-cost, commodity SSD’s are equivalent in performance and availability to purpose built flash modules. But that’s not the case. So what makes purpose built Flash modules different from commodity SSD’s?  A good example of purpose built flash is the Hitachi Data Systems FMD (Flash Module) which is incorporated into F-Series all-flash arrays.  These purpose built modules incorporate custom microprocessors or “ASIC’s”, that maximizes flash performance while delivering enterprise-class availability. In fact, Hitachi’s FMD accelerated flash delivers five times the write performance and three times the read performance of commodity SSD’s. Hitachi FMD’s are intelligent in that background process are handled and prioritized on the FMD, not on the host.  By removing housekeeping tasks from the I/O path, the infamous "write cliff" is eliminated. As a result, response times will stay consistently fast even as capacity fills up an FMD. Consequently you don’t have to choose between sustained performance and capacity. Having to make this choice is an inherent issue with SSD’s that has been resolved with the addition of Hitachi’s patented flash algorithms which run directly on the FMD.  In addition; the FMD modules are tightly integrated with Hitachi’s Storage Virtualization Operating System (SVOS) which enables the adaptive optimization of flash operations under all conditions. For example, data compression can be done directly on the FMD’s without taxing the storage controllers.  This results in data reduction that is penalty-free or done without any trade off in performance.


This table provides more technical look at Hitachi’s Accelerated FMD module, and the benefits they provide over typical commodity SSD’s.



Choose Your Flash Partner Carefully… Very Carefully
The flash landscape is littered with flash vendors who over promise and under deliver.  This is evidenced by recent number of critical Flash outages spotlighted by the IT press. What’s more troublesome is the prospect of partnering with a vendor who is hemorrhaging money .  You have to ask yourself, will they be here to support my business in the future? Will they be purchased by an indifferent parent company or go out of business altogether?  Another point to consider is how confident is the vendors commitment to you regarding their flash technology?  Hitachi Data Systems (HDS) offers the industry’s only 100% Data Availability Guarantee assuring that your flash deployment will deliver enterprise-class availability.  As a primary technology supplier, HDS has over 350 patents in flash technology. HDS VSP flash is used to support mission critical Hitachi technology including healthcare systems, nuclear power, rail transport, and financial systems.  No matter who you are considering as you modernize with all-flash solutions, do your homework, prioritize your workloads, and choose a vendor with solid expertise and a demonstrated track record of high availability in mission critical environments.


Learn More:   Video-Hitachi and Storage Switzerland discuss the Benefits of Flash Modules