Welcome!

SDN Journal Authors: Elizabeth White, Liz McMillan, Stefan Bernbo, Pat Romanski, TJ Randall

Related Topics: Containers Expo Blog, Java IoT, Microservices Expo, @CloudExpo, @BigDataExpo, SDN Journal

Containers Expo Blog: Article

SSD vs. HDD – The Battle for the Future of Storage

Look to the latest economically sensible storage solutions that are answering today’s performance and capacity calls

I have been working for technology companies for 33 years now, so I don't know why I'm always surprised at the technology myths that proliferate. For example, there is a popular notion running around that Solid State Drives (SSDs) will replace Hard Disk Drives (HDDs) as the dominant storage media. So, which will win? Let me give you my answer upfront before I take you through my arguments: both win, and the market size for both continues to grow.

As I offer up this data and this perspective, I'll repeat some advice I received early in my career. A mentor once told me, when searching for the truth in business and technology "look to the economics" (maybe my version of "go to the mattresses" for you "Godfather" fans).

Here is what I read and hear on a regular basis regarding the battle of HDDs and SSDs:

  • SSDs run circles around HDDs for performance
  • SSDs will soon replace HDDs
  • The improving density of SSDs will collapse the current cost premium to HDDs

Sound familiar? Well, as with most claims of this ilk, there are some elements of truth to them but each of these statements goes too far when viewed in light of some data.

Performance
Yes, it's true that SSDs are fundamentally faster than HDDs. This is particularly true of random I/O data reading (as with databases). With large block sequential data (i.e., rich media like video), however, this difference tends to be very small.

Replacing HDD?
Here's a claim where the data just doesn't add up. While the attractiveness of the SSD technology would lead one to believe this, the economics really don't hold up. I should probably point more specifically to NAND flash here (the "solid state" in SSDs) because another solid state technology might actually achieve this, but that appears to be years and tens of billions of dollars away.

Let's talk for a minute about the world's demand for storage. Last year approximately 2500 exabytes of data was created and/or replicated. And...this is doubling about every two years. This needs to be serviced largely by HDDs and SSDs. Last year, the NAND flash industry produced somewhere between 30 and 40 exabytes of storage; with somewhere around 3.5 exabytes finding its way into SSDs (the balance in phones, tablets, cameras, etc.). What is that, 1.4% of our total storage need? But production is ramping up... at a capital cost of about $1.5 billion per Exabyte (semiconductor fabs are expensive)! So, from an available supply perspective, SSDs replacing HDDs seems implausible.

Improving Technology Makes SSDs Cheaper
Agree. The NAND flash technology point is at 21nm line widths with plans to move to 19, then 16 nm. Storage density is further improving with the use of multi-level cell (MLC) capabilities vs single-level cell (SLC). This is bringing down the cost of solid state storage in much the same way the areal density increases seen in HDDs brought down the cost of hard drive storage.

Notice how I said "brought" down (i.e., past tense)? Because a real density growth in the hard drive industry has slowed to a crawl, the rapid erosion of cost/Gb has also slowed to a crawl. Now, the HDD industry needs to move to its next technology (HAMR?) to continue to take cost out and HAMR is a number of years away. HAMR will require significant capital investment by the HDD companies. Significant capital investment will be required anyway to keep up with storage demand (even more so with slowing areal density growth). This all spells out a flattening of HDD costs for the foreseeable future. Some would speculate that a renewed interest in improving the utilization of HDD capacity is an artifact of these economics.

Here's what's preventing the complete collapse of the price difference between the two technologies. The NAND flash suppliers have a similar problem as the HDD manufacturers... the implications of shrinking technology geometries. As the line widths shrink, the ability of flash to sustain multiple write-erase cycles declines. To make up for this deficiency, sophisticated error-correction algorithms and "brute force" overprovisioning (to allow some cells to wear out) are being used. This and the above mentioned semiconductor fab costs tend to mitigate the progress SSDs are making in closing the cost gap to HDDs.

Having made my arguments that SSDs won't take over the world, I have to say that IT solutions need this technology. I think you can see that SSDs aren't the answer to all our storage needs, but they allow us to address a crying storage requirement. At a high level, storage is called on to produce two key deliverables:

  • Make data available to an application or user in an appropriate timeframe (i.e., performance) and in today's environment this need is growing.
  • Store data reliably (i.e., capacity) and in today's environment this need is growing

By and large, to date, systems with hard drives have been architected to deliver both of these capabilities. It's hard to argue that hard drives haven't done a good job of delivering affordable capacity. But to deliver against the performance requirements of IT solutions, hard drives:

  • Have been developed with higher speeds, but arguably little progress has been made in the last ten years
  • Have been "short stroked" (a technique limiting the stroke of the actuator to improve performance)
  • Have been grouped together to allow striping of data across a large number of drives to aggregate their performance.

With each of these approaches the user suffers from higher power requirements, and with the last two approaches their system has been overprovisioned (leaving stranded capacity) to deliver performance. This all adds up to significant system cost that can be avoided with new storage architectures.

Here's where SSDs come in. SSDs are proving to be a technology answer to the new generation of storage needs, both the growing performance and the growing capacity requirements. Here's the simple, logical way to think about SSDs and HDDs and their role in storage solutions. Use the right tool for the job. That is, take advantage of SSDs for performance (particularly small block, random I/O) and HDDs for capacity.

You might challenge me now and ask, "Does adding SSDs (Flash) to IT solutions make economic sense?" SSDs are expensive, but, used appropriately, SSDs can also minimize the number of HDDs required in a given solution. The secret is in optimizing the use of both, that is, avoid overprovisioning of both. Thin provisioning of capacity has become popular as a cost saver. Similarly, thin provisioning of performance is a similar cost saver. (This is a benefit of virtualized caching or tiering capabilities of newer storage solutions.)

I'll close with a few proof points. Look to the latest economically sensible storage solutions that are answering today's performance and capacity calls. The vast majority of affordable "Ultrabooks" incorporate both flash and hard drive technology, as does Apple's latest "Fusion" drive.

More Stories By Tom Major

Tom Major is President of Starboard Storage. He joined Starboard from Seagate Technology, where he was senior vice president of Product Management and Business Operations. Before Seagate, Major worked at LeftHand Networks as chief strategy officer. Previous positions included vice president and general manager, Disk Business Unit, at StorageTek and vice president of Network Storage Marketing at HP, where he spent 21 years.

Comments (0)

Share your thoughts on this story.

Add your comment
You must be signed in to add a comment. Sign-in | Register

In accordance with our Comment Policy, we encourage comments that are on topic, relevant and to-the-point. We will remove comments that include profanity, personal attacks, racial slurs, threats of violence, or other inappropriate material that violates our Terms and Conditions, and will block users who make repeated violations. We ask all readers to expect diversity of opinion and to treat one another with dignity and respect.


@CloudExpo Stories
Internet of @ThingsExpo has announced today that Chris Matthieu has been named tech chair of Internet of @ThingsExpo 2017 New York The 7th Internet of @ThingsExpo will take place on June 6-8, 2017, at the Javits Center in New York City, New York. Chris Matthieu is the co-founder and CTO of Octoblu, a revolutionary real-time IoT platform recently acquired by Citrix. Octoblu connects things, systems, people and clouds to a global mesh network allowing users to automate and control design flo...
"We are an all-flash array storage provider but our focus has been on VM-aware storage specifically for virtualized applications," stated Dhiraj Sehgal of Tintri in this SYS-CON.tv interview at 19th Cloud Expo, held November 1-3, 2016, at the Santa Clara Convention Center in Santa Clara, CA.
With 15% of enterprises adopting a hybrid IT strategy, you need to set a plan to integrate hybrid cloud throughout your infrastructure. In his session at 18th Cloud Expo, Steven Dreher, Director of Solutions Architecture at Green House Data, discussed how to plan for shifting resource requirements, overcome challenges, and implement hybrid IT alongside your existing data center assets. Highlights included anticipating workload, cost and resource calculations, integrating services on both sides...
Unless your company can spend a lot of money on new technology, re-engineering your environment and hiring a comprehensive cybersecurity team, you will most likely move to the cloud or seek external service partnerships. In his session at 18th Cloud Expo, Darren Guccione, CEO of Keeper Security, revealed what you need to know when it comes to encryption in the cloud.
"We're a cybersecurity firm that specializes in engineering security solutions both at the software and hardware level. Security cannot be an after-the-fact afterthought, which is what it's become," stated Richard Blech, Chief Executive Officer at Secure Channels, in this SYS-CON.tv interview at @ThingsExpo, held November 1-3, 2016, at the Santa Clara Convention Center in Santa Clara, CA.
According to Forrester Research, every business will become either a digital predator or digital prey by 2020. To avoid demise, organizations must rapidly create new sources of value in their end-to-end customer experiences. True digital predators also must break down information and process silos and extend digital transformation initiatives to empower employees with the digital resources needed to win, serve, and retain customers.
"We are the public cloud providers. We are currently providing 50% of the resources they need for doing e-commerce business in China and we are hosting about 60% of mobile gaming in China," explained Yi Zheng, CPO and VP of Engineering at CDS Global Cloud, in this SYS-CON.tv interview at 19th Cloud Expo, held November 1-3, 2016, at the Santa Clara Convention Center in Santa Clara, CA.
The WebRTC Summit New York, to be held June 6-8, 2017, at the Javits Center in New York City, NY, announces that its Call for Papers is now open. Topics include all aspects of improving IT delivery by eliminating waste through automated business models leveraging cloud technologies. WebRTC Summit is co-located with 20th International Cloud Expo and @ThingsExpo. WebRTC is the future of browser-to-browser communications, and continues to make inroads into the traditional, difficult, plug-in web co...
Between 2005 and 2020, data volumes will grow by a factor of 300 – enough data to stack CDs from the earth to the moon 162 times. This has come to be known as the ‘big data’ phenomenon. Unfortunately, traditional approaches to handling, storing and analyzing data aren’t adequate at this scale: they’re too costly, slow and physically cumbersome to keep up. Fortunately, in response a new breed of technology has emerged that is cheaper, faster and more scalable. Yet, in meeting these new needs they...
When it comes to cloud computing, the ability to turn massive amounts of compute cores on and off on demand sounds attractive to IT staff, who need to manage peaks and valleys in user activity. With cloud bursting, the majority of the data can stay on premises while tapping into compute from public cloud providers, reducing risk and minimizing need to move large files. In his session at 18th Cloud Expo, Scott Jeschonek, Director of Product Management at Avere Systems, discussed the IT and busin...
The Internet of Things (IoT) promises to simplify and streamline our lives by automating routine tasks that distract us from our goals. This promise is based on the ubiquitous deployment of smart, connected devices that link everything from industrial control systems to automobiles to refrigerators. Unfortunately, comparatively few of the devices currently deployed have been developed with an eye toward security, and as the DDoS attacks of late October 2016 have demonstrated, this oversight can ...
What happens when the different parts of a vehicle become smarter than the vehicle itself? As we move toward the era of smart everything, hundreds of entities in a vehicle that communicate with each other, the vehicle and external systems create a need for identity orchestration so that all entities work as a conglomerate. Much like an orchestra without a conductor, without the ability to secure, control, and connect the link between a vehicle’s head unit, devices, and systems and to manage the ...
"Once customers get a year into their IoT deployments, they start to realize that they may have been shortsighted in the ways they built out their deployment and the key thing I see a lot of people looking at is - how can I take equipment data, pull it back in an IoT solution and show it in a dashboard," stated Dave McCarthy, Director of Products at Bsquare Corporation, in this SYS-CON.tv interview at @ThingsExpo, held November 1-3, 2016, at the Santa Clara Convention Center in Santa Clara, CA.
In his session at Cloud Expo, Robert Cohen, an economist and senior fellow at the Economic Strategy Institute, provideed economic scenarios that describe how the rapid adoption of software-defined everything including cloud services, SDDC and open networking will change GDP, industry growth, productivity and jobs. This session also included a drill down for several industries such as finance, social media, cloud service providers and pharmaceuticals.
In IT, we sometimes coin terms for things before we know exactly what they are and how they’ll be used. The resulting terms may capture a common set of aspirations and goals – as “cloud” did broadly for on-demand, self-service, and flexible computing. But such a term can also lump together diverse and even competing practices, technologies, and priorities to the point where important distinctions are glossed over and lost.
Data is the fuel that drives the machine learning algorithmic engines and ultimately provides the business value. In his session at Cloud Expo, Ed Featherston, a director and senior enterprise architect at Collaborative Consulting, discussed the key considerations around quality, volume, timeliness, and pedigree that must be dealt with in order to properly fuel that engine.
All clouds are not equal. To succeed in a DevOps context, organizations should plan to develop/deploy apps across a choice of on-premise and public clouds simultaneously depending on the business needs. This is where the concept of the Lean Cloud comes in - resting on the idea that you often need to relocate your app modules over their life cycles for both innovation and operational efficiency in the cloud. In his session at @DevOpsSummit at19th Cloud Expo, Valentin (Val) Bercovici, CTO of Soli...
SYS-CON Events announced today that Dataloop.IO, an innovator in cloud IT-monitoring whose products help organizations save time and money, has been named “Bronze Sponsor” of SYS-CON's 20th International Cloud Expo®, which will take place on June 6-8, 2017, at the Javits Center in New York City, NY. Dataloop.IO is an emerging software company on the cutting edge of major IT-infrastructure trends including cloud computing and microservices. The company, founded in the UK but now based in San Fran...
Join Impiger for their featured webinar: ‘Cloud Computing: A Roadmap to Modern Software Delivery’ on November 10, 2016, at 12:00 pm CST. Very few companies have not experienced some impact to their IT delivery due to the evolution of cloud computing. This webinar is not about deciding whether you should entertain moving some or all of your IT to the cloud, but rather, a detailed look under the hood to help IT professionals understand how cloud adoption has evolved and what trends will impact th...
In his session at 19th Cloud Expo, Claude Remillard, Principal Program Manager in Developer Division at Microsoft, contrasted how his team used config as code and immutable patterns for continuous delivery of microservices and apps to the cloud. He showed how the immutable patterns helps developers do away with most of the complexity of config as code-enabling scenarios such as rollback, zero downtime upgrades with far greater simplicity. He also demoed building immutable pipelines in the cloud ...