Welcome!

Linux Authors: Carmen Gonzalez, Liz McMillan, Liz Dickinson, Trevor Parsons, Anne Buff

Related Topics: Virtualization, Java, SOA & WOA, Linux, Open Source, SDN Journal

Virtualization: Article

Preventing Performance Bottlenecks with Inline Deduplication

In a typical enterprise storage system the bottleneck to performance is in media bandwidth or computational overhead

Implementing high performance in enterprise storage is a constant battle to find and eliminate the next system bottleneck. Normally this alternates between limits of the underlying media and the computational overhead of metadata management, but choosing the wrong approach to deduplication can introduce a third performance challenge that can be impossible to overcome. Storage that implements a multi-pass approach to data optimization, such as staged or post-process deduplication, becomes inherently at a disadvantage for both computational and media overhead.

Common Performance Bottlenecks
In a typical enterprise storage system the bottleneck to performance is in one of two places: media bandwidth or computational overhead.

For the storage system designer, media overhead is the simplest to address - add more or faster media. In a hard disk-based storage system, this means adding faster drives, more drives, and larger drive sets. In a flash storage system bandwidth is increased by using SLC flash, adding more independent modules, allocating more over-provisioned space, and improving the flash translation layer.

Reducing computational overhead is a greater challenge. Once you have enough media bandwidth the problem becomes shuffling data to and from the storage initiators. Identifying the bottlenecks to performance here can be devilishly complex, as the designer must be concerned about matters such as system memory bandwidth, number of data copies and, especially in today's multi-core world, synchronization between multiple requests. There's no silver bullet here, so the only solution is having a very talented team of software engineers designing and optimizing the storage platform.

Adding deduplication introduces complexity directly into this most challenging area for performance improvement. Any deduplication implementation must interact directly with the storage metadata that is so critical to performance, since I/O requests are being redirected or eliminated based on the system's knowledge of duplicate data. Unless the deduplication technology has been designed and implemented in an inline, multi-core scalable, and low memory overhead way, system architects often try to separate deduplication into a separate layer and a second pass through the data. This is a mistake that harms storage performance in a way that cannot be repaired.

The Impossible Challenge of Multi-Pass Deduplication
This second pass through the data commonly occurs in two possible places: on the final storage media or when transferring data from a staging area to the final storage media.

The first case is always called post-process deduplication. Data are written to their resting media location and a separate process later reads them back, as time and bandwidth allow, determining if any portions are duplicates. If there are duplicates then storage metadata is updated to note this and space is freed for reuse. I've written extensively in the past about the risks of post-process deduplication; since it always requires additional media bandwidth and computational overhead it severely harms performance, and since there are no guarantees about when deduplication will occur it does not meet the requirements for high-change-rate use cases such as VDI.

Post-process Deduplication

The second case, where data is deduplicated as it is being moved from a staging location to a final media location, is often erroneously called inline - as it is inline with that destaging process - but is really just a modified form of post-process deduplication. As with conventional post-process deduplication, another round of data read and processing must occur. Additionally, now both the staging media and final media must provide the full system level of performance or either can become the bottleneck.

For example, some flash storage systems stage all data to a small arena of SLC flash prior to deduplication. This design doubles the number of possible performance bottlenecks in the architecture: performance writing to the staging area, front-end data ingestion, final media storage performance, and the deduplication and de-staging process itself. This sort of multi-pass deduplication process retains all of the negative performance aspects of a traditional post-process implementation.

Staged Post-process Deduplication

High Performance Requires Inline Deduplication
Any form of multi-pass deduplication introduces new bottlenecks that prevent an enterprise storage system from delivering the highest levels of performance. Post-process deduplication, whether on the final media or during a destaging process, creates additional overhead in both media access and data processing. For flash storage platforms requiring the highest levels of performance, only tightly integrated inline deduplication can meet all system requirements.

More Stories By Jered Floyd

Jered Floyd, Chief Technology Officer and Founder of Permabit Technology Corporation, is responsible for exploring strategic future directions for Permabit’s products, and providing thought leadership to guide the company’s data optimization initiatives. He has previously deployed Permabit’s effective software development methodologies and was responsible for developing Permabit product’s core protocol and initial server and system architectures.

Prior to Permabit, Floyd was a Research Scientist on the Microbial Engineering project at the MIT Artificial Intelligence Laboratory, working to bridge the gap between biological and computational systems. Earlier at Turbine, he developed a robust integration language for managing active objects in a massively distributed online virtual environment. Floyd holds Bachelor’s and Master’s degrees in Electrical Engineering and Computer Science from the Massachusetts Institute of Technology.

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.


@ThingsExpo Stories
SYS-CON Events announced today that SOA Software, an API management leader, will exhibit at SYS-CON's 15th International Cloud Expo®, which will take place on November 4–6, 2014, at the Santa Clara Convention Center in Santa Clara, CA. SOA Software is a leading provider of API Management and SOA Governance products that equip business to deliver APIs and SOA together to drive their company to meet its business strategy quickly and effectively. SOA Software’s technology helps businesses to accelerate their digital channels with APIs, drive partner adoption, monetize their assets, and achieve a...
SYS-CON Events announced today that Aria Systems, the recurring revenue expert, has been named "Bronze Sponsor" of SYS-CON's 15th International Cloud Expo®, which will take place on November 4-6, 2014, at the Santa Clara Convention Center in Santa Clara, CA. Aria Systems helps leading businesses connect their customers with the products and services they love. Industry leaders like Pitney Bowes, Experian, AAA NCNU, VMware, HootSuite and many others choose Aria to power their recurring revenue business and deliver exceptional experiences to their customers.
SYS-CON Events announced today that AgilePoint, the leading provider of Microsoft-centric Business Process Management software, will exhibit at SYS-CON's 2nd International @ThingsExpo which will take place on November 4–6, 2014, at the Santa Clara Convention Center in Santa Clara, CA. AgilePoint is the leading provider of Microsoft-based Business Process Management (BPM) software products, has 1,300+ on-premise and cloud deployments in 25+ countries and provides the same advanced BPM feature set as J2EE vendors like IBM and Appian for the Microsoft .NET native environment. AgilePoint customer...
The Internet of Things (IoT) promises to evolve the way the world does business; however, understanding how to apply it to your company can be a mystery. Most people struggle with understanding the potential business uses or tend to get caught up in the technology, resulting in solutions that fail to meet even minimum business goals. In his session at Internet of @ThingsExpo, Jesse Shiah, CEO / President / Co-Founder of AgilePoint Inc., will show what is needed to leverage the IoT to transform your business. He will discuss opportunities and challenges ahead for the IoT from a market and tec...
SYS-CON Events announced today that Utimaco will exhibit at SYS-CON's 15th International Cloud Expo®, which will take place on November 4–6, 2014, at the Santa Clara Convention Center in Santa Clara, CA. Utimaco is a leading manufacturer of hardware based security solutions that provide the root of trust to keep cryptographic keys safe, secure critical digital infrastructures and protect high value data assets. Only Utimaco delivers a general-purpose hardware security module (HSM) as a customizable platform to easily integrate into existing software solutions, embed business logic and build s...
One of the biggest challenges when developing connected devices is identifying user value and delivering it through successful user experiences. In his session at Internet of @ThingsExpo, Mike Kuniavsky, Principal Scientist, Innovation Services at PARC, will describe an IoT-specific approach to user experience design that combines approaches from interaction design, industrial design and service design to create experiences that go beyond simple connected gadgets to create lasting, multi-device experiences grounded in people’s real needs and desires.
Samsung VP Jacopo Lenzi, who headed the company's recent SmartThings acquisition under the auspices of Samsung's Open Innovaction Center (OIC), answered a few questions we had about the deal. This interview was in conjunction with our interview with SmartThings CEO Alex Hawkinson. IoT Journal: SmartThings was developed in an open, standards-agnostic platform, and will now be part of Samsung's Open Innovation Center. Can you elaborate on your commitment to keep the platform open? Jacopo Lenzi: Samsung recognizes that true, accelerated innovation cannot be driven from one source, but requires a...
The Internet of Things will greatly expand the opportunities for data collection and new business models driven off of that data. In her session at Internet of @ThingsExpo, Esmeralda Swartz, CMO of MetraTech, will discuss how for this to be effective you not only need to have infrastructure and operational models capable of utilizing this new phenomenon, but increasingly service providers will need to convince a skeptical public to participate. Get ready to show them the money! Speaker Bio: Esmeralda Swartz, CMO of MetraTech, has spent 16 years as a marketing, product management, and busin...
SYS-CON Events announced today that TeleStax, the main sponsor of Mobicents, will exhibit at Internet of @ThingsExpo, which will take place on November 4–6, 2014, at the Santa Clara Convention Center in Santa Clara, CA. TeleStax provides Open Source Communications software and services that facilitate the shift from legacy SS7 based IN networks to IP based LTE and IMS networks hosted on private (on-premise), hybrid or public clouds. TeleStax products include Restcomm, JSLEE, SMSC Gateway, USSD Gateway, SS7 Resource Adaptors, SIP Servlets, Rich Multimedia Services, Presence Services/RCS, Diame...
Things are being built upon cloud foundations to transform organizations. This CEO Power Panel at 15th Cloud Expo, moderated by Roger Strukhoff, Cloud Expo and @ThingsExpo conference chair, will address the big issues involving these technologies and, more important, the results they will achieve. How important are public, private, and hybrid cloud to the enterprise? How does one define Big Data? And how is the IoT tying all this together?
We certainly live in interesting technological times. And no more interesting than the current competing IoT standards for connectivity. Various standards bodies, approaches, and ecosystems are vying for mindshare and positioning for a competitive edge. It is clear that when the dust settles, we will have new protocols, evolved protocols, that will change the way we interact with devices and infrastructure. We will also have evolved web protocols, like HTTP/2, that will be changing the very core of our infrastructures. At the same time, we have old approaches made new again like micro-services...
The only place to be June 9-11 is Cloud Expo & @ThingsExpo 2015 East at the Javits Center in New York City. Join us there as delegates from all over the world come to listen to and engage with speakers & sponsors from the leading Cloud Computing, IoT & Big Data companies. Cloud Expo & @ThingsExpo are the leading events covering the booming market of Cloud Computing, IoT & Big Data for the enterprise. Speakers from all over the world will be hand-picked for their ability to explore the economic strategies that utility/cloud computing provides. Whether public, private, or in a hybrid form, clo...
SYS-CON Events announces a new pavilion on the Cloud Expo floor where WebRTC converges with the Internet of Things. Pavilion will showcase WebRTC and the Internet of Things. The Internet of Things (IoT) is the most profound change in personal and enterprise IT since the creation of the Worldwide Web more than 20 years ago. All major researchers estimate there will be tens of billions devices--computers, smartphones, tablets, and sensors – connected to the Internet by 2020. This number will continue to grow at a rapid pace for the next several decades.
SYS-CON Events announced today that Gridstore™, the leader in software-defined storage (SDS) purpose-built for Windows Servers and Hyper-V, will exhibit at SYS-CON's 15th International Cloud Expo®, which will take place on November 4–6, 2014, at the Santa Clara Convention Center in Santa Clara, CA. Gridstore™ is the leader in software-defined storage purpose built for virtualization that is designed to accelerate applications in virtualized environments. Using its patented Server-Side Virtual Controller™ Technology (SVCT) to eliminate the I/O blender effect and accelerate applications Gridsto...
SYS-CON Events announced today that Red Hat, the world's leading provider of open source solutions, will exhibit at Internet of @ThingsExpo, which will take place on November 4–6, 2014, at the Santa Clara Convention Center in Santa Clara, CA. Red Hat is the world's leading provider of open source software solutions, using a community-powered approach to reliable and high-performing cloud, Linux, middleware, storage and virtualization technologies. Red Hat also offers award-winning support, training, and consulting services. As the connective hub in a global network of enterprises, partners, a...
As the Internet of Things unfolds, mobile and wearable devices are blurring the line between physical and digital, integrating ever more closely with our interests, our routines, our daily lives. Contextual computing and smart, sensor-equipped spaces bring the potential to walk through a world that recognizes us and responds accordingly. We become continuous transmitters and receivers of data. In his session at Internet of @ThingsExpo, Andrew Bolwell, Director of Innovation for HP’s Printing and Personal Systems Group, will discuss how key attributes of mobile technology – touch input, senso...
The Internet of Things (IoT) is making everything it touches smarter – smart devices, smart cars and smart cities. And lucky us, we’re just beginning to reap the benefits as we work toward a networked society. However, this technology-driven innovation is impacting more than just individuals. The IoT has an environmental impact as well, which brings us to the theme of this month’s #IoTuesday Twitter chat. The ability to remove inefficiencies through connected objects is driving change throughout every sector, including waste management. BigBelly Solar, located just outside of Boston, is trans...
Connected devices and the Internet of Things are getting significant momentum in 2014. In his session at Internet of @ThingsExpo, Jim Hunter, Chief Scientist & Technology Evangelist at Greenwave Systems, will examine three key elements that together will drive mass adoption of the IoT before the end of 2015. The first element is the recent advent of robust open source protocols (like AllJoyn and WebRTC) that facilitate M2M communication. The second is broad availability of flexible, cost-effective storage designed to handle the massive surge in back-end data in a world where timely analytics...
Internet of @ThingsExpo Silicon Valley announced on Thursday its first 12 all-star speakers and sessions for its upcoming event, which will take place November 4-6, 2014, at the Santa Clara Convention Center in California. @ThingsExpo, the first and largest IoT event in the world, debuted at the Javits Center in New York City in June 10-12, 2014 with over 6,000 delegates attending the conference. Among the first 12 announced world class speakers, IBM will present two highly popular IoT sessions, which will take place November 4-6, 2014 at the Santa Clara Convention Center in Santa Clara, Calif...
From a software development perspective IoT is about programming "things," about connecting them with each other or integrating them with existing applications. In his session at @ThingsExpo, Yakov Fain, co-founder of Farata Systems and SuranceBay, will show you how small IoT-enabled devices from multiple manufacturers can be integrated into the workflow of an enterprise application. This is a practical demo of building a framework and components in HTML/Java/Mobile technologies to serve as a platform that can integrate new devices as they become available on the market.