Welcome!

XML Authors: Pat Romanski, Liz McMillan, Anne Buff, Carmen Gonzalez, Sanjeev Sharma

Related Topics: Cloud Expo, SOA & WOA

Cloud Expo: Blog Feed Post

Applying Scalability Patterns to Infrastructure Architecture

Too often software design patterns are overlooked by network and application delivery network architects

Too often software design patterns are overlooked by network and application delivery network architects but these patterns are often equally applicable to addressing a broad range of architectural challenges in the application delivery tier of the data center.

The “High Scalability” blog is fast becoming one of my favorite reads. Last week did not disappoint with a post highlighting a set of scalability design patterns that was, apparently, inspired by yet another High Scalability post on “6 Ways to Kill Your Servers: Learning to Scale the Hard Way.

cheese-curds
Credit:Michael Chow/azcentral.com

This particular post caught my attention primarily because although I’ve touched on many of these patterns in the past, I’ve never thought to call them

what they are: scalability patterns. That’s probably a side-effect of forgetting that building an architecture of any kind is at its core computer science and thus algorithms and design patterns are applicable to both micro- and macro-architectures, such as those used when designing a scalable architecture.

This is actually more common than you’d think, as it’s rarely the case that a network guy and a developer sit down and discuss scalability patterns over beer and deep fried cheese curds (hey, I live in Wisconsin and it’s my blog post so just stop making faces until you’ve tried it). Developers and architects sit over there and think about how to design a scalable application from the perspective of its components – databases, application servers, middleware, etc… Network architects sit over here and think about how to scale an application from the perspective of network components – load balancers, trunks, VLANs, and switches. The thing is that the scalability patterns leveraged by developers and architects can almost universally be abstracted and applied to the application delivery network – the set of components integrated as a means to ensure availability, performance, and security of applications. That’s why devops is so important and why devops has to bring dev into ops as much as its necessary to bring some ops into dev. There needs to be more cross-over, more discussion, between the two groups if not an entirely new group in order to leverage the knowledge and skills that each has in new and innovative ways.

ABSTRACT and APPLY

So the aforementioned post is just a summary of a longer and more detailed post, but for purposes of this post I think the summary will do with the caveat that the original, “Scalability patterns and an interesting story...” by Jesper Söderlund is a great read that should definitely be on your “to read” list in the very near future.

For now, let’s briefly touch on the scalability patterns and sub-patterns Jesper described with some commentary on how they fit into scalability from a network and application delivery network perspective. The original text from the High Scalability blog are in red(dish) text.

  • Load distribution - Spread the system load across multiple processing units

    This is a horizontal scaling strategy that is well-understood. It may take the form of “clustering” or “load balancing” but in both cases it is essentially an aggregation coupled with a distributed processing model. The secret sauce is almost always in the way in which the aggregation point (strategic point of control) determines how best to distribute the load across the “multiple processing units.”  
    • load balancing / load sharing - Spreading the load across many components with equal properties for handling the request
      This is what most people think of when they hear “load balancing”, it’s just that at the application delivery layer we think in terms of directing application requests (usually HTTP but can just about any application protocol) to equal “servers” (physical or virtual) that handle the request. This is a “scaling out” approach that is most typically associated today with cloud computing and auto-scaling: launch additional clones of applications as virtual instances in order to increase the total capacity of an application. The load balancing distributes requests across all instances based on the configured load balancing algorithm.
    • Partitioning - Spreading the load across many components by routing an individual request to a component that owns that data specific
      This is really where the architecture comes in and where efficiency and performance can be dramatically increased in an image application delivery architecture. Rather than each instance of an application being identical to every other one, each instance (or pool of instances) is designated as the “owner”. This allows for devops to tweak configurations of the underlying operating system, web and application server software for the specific type of request being handled. This is, also, where the difference between “application switching” and “load balancing” becomes abundantly clear as “application switching” is used as a means to determine where to route a particular request which is/can be then load balanced across a pool of resources. It’s a subtle distinction but an important one when architecting not only efficient and fast but resilient and reliable delivery networks.
          • Vertical partitioning - Spreading the load across the functional boundaries of a problem space, separate functions being handled by different processing units
            When it comes to routing application requests we really don’t separate by function unless that function is easily associated with a URI. The most common implementation of vertical partitioning at the application switching layer will be by content. Example: creating resource pools based on the Content-Type HTTP header: images in pool “image servers” and content in pool “content servers”. This allows for greater optimization of the web/application server based on the usage pattern and the content type, which can often also be related to a range of sizes. This also, in a distributed environment, allows architects to leverage say cloud-based storage for static content while maintaining dynamic content (and its associated data stores) on-premise. This kind of hybrid cloud strategy has been postulated as one of the most common use cases since the first wispy edges of cloud were seen on the horizon.
          • Horizontal partitioning - Spreading a single type of data element across many instances, according to some partitioning key, e.g. hashing the player id and doing a modulus operation, etc. Quite often referred to as sharding.
            This sub-pattern is inline with the way in which persistence-based load balancing is accomplished, as well as the handling of object caching. This also describes the way in which you might direct requests received from specific users to designated instances that are specifically designed to handle their unique needs or requirements, such as the separation of “gold” users from “free” users based on some partitioning key which in HTTP land is often a cookie containing the relevant data.
    • Queuing and batch - Achieve efficiencies of scale by processing batches of data, usually because the overhead of an operation is amortized across multiple request 
      I admit defeat in applying this sub-pattern to application delivery. I know, you’re surprised, but this really is very specific to middleware and aside from the ability to leverage queuing for Quality of Service (QoS) at the delivery layer this one is just not fitting in well. If you have an idea how this fits, feel free to let me know – I’d love to be able to apply all the scalability patterns and sub-patterns to a broader infrastructure architecture.
      • Relaxing of data constraints - Many different techniques and trade-offs with regards to the immediacy of processing / storing / access to data fall in this strategy
        This one takes us to storage virtualization and tiering and the way in which data storage and access is intelligently handled in varying properties based on usage and prioritization of the content. If one relaxes the constraints around access times for certain types of data, it is possible to achieve a higher efficiency use of storage by subjugating some content to secondary and tertiary tiers which may not have the same performance attributes as your primary storage tier. And make no mistake, storage virtualization is a part of the application delivery network – has been since its inception – and as cloud computing and virtualization have grown so has the importance of a well-defined storage tiering strategy.

        We can bring this back up to the application layer by considering that a relaxation of data constraints with regards to immediacy of access can be applied by architecting a solution that separates data reads from writes. This implies eventual consistency, as data updated/written to one database must necessarily be replicated to the databases from which reads are, well, read, but that’s part of relaxing a data constraint. This is a technique used by many large, social sites such as Facebook and Plenty of Fish in order to scale the system to the millions upon millions of requests it handles in any given hour.
      • Parallelization - Work on the same task in parallel on multiple processing units
        I’m not going to be able to apply this one either, unless it was in conjunction with optimizing something like MapReduce and SPDY. I’ve been thinking hard about this one, and the problem is the implication that “same task” is really the “same task”, and that processing is distributed. That said, if the actual task can be performed by multiple processing units, then an application delivery controller could certainly be configured to recognize that a specific URL should be essentially sent to some other proxy/solution that performs the actual distribution, but the processing model here deviates sharply from the request-reply paradigm under which most applications today operate.

    DEVOPS CAN MAKE THIS HAPPEN

    I hate to sound-off too much on the “devops” trumpet, but one of the primary ways in which devops will be of significant value in the future is exactly in this type of practical implementation. Only by recognizing that many architectural patterns are applicable to not only application but infrastructure architecture can we start to apply a whole lot of “lessons that have already been learned” by developers and architects to emerging infrastructure architectural models. This abstraction and application from well-understood patterns in application design and architecture will be invaluable in designing the new network; the next iteration of network theory and implementation that will allow it to scale along with the applications it is delivering.


    Related blogs & articles:


    Follow me on Twitter View Lori's profile on SlideShare friendfeed icon_facebook

    AddThis Feed Button Bookmark and Share

    Read the original blog entry...

    More Stories By Lori MacVittie

    Lori MacVittie is responsible for education and evangelism of application services available across F5’s entire product suite. Her role includes authorship of technical materials and participation in a number of community-based forums and industry standards organizations, among other efforts. MacVittie has extensive programming experience as an application architect, as well as network and systems development and administration expertise. Prior to joining F5, MacVittie was an award-winning Senior Technology Editor at Network Computing Magazine, where she conducted product research and evaluation focused on integration with application and network architectures, and authored articles on a variety of topics aimed at IT professionals. Her most recent area of focus included SOA-related products and architectures. She holds a B.S. in Information and Computing Science from the University of Wisconsin at Green Bay, and an M.S. in Computer Science from Nova Southeastern University.

    @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.
    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...
    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...
    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...
    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.
    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 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.