Welcome!

DevOps Journal Authors: Sandi Mappic, Trevor Parsons, Carmen Gonzalez, Jackie Kahle, Rex Morrow, Datical

Related Topics: DevOps Journal, Java, Linux, Cloud Expo, Big Data Journal, SDN Journal

DevOps Journal: Blog Feed Post

@DevOps Summit | Why Scaling Down Is Harder Than Scaling Up [#DevOps]

Elasticity should be non-disruptive

Elasticity is hailed as one of the biggest benefits of cloud and software-defined architectures. It's more efficient than traditional scalability models that only went one direction: up. It's based on the premise that wasting money and resources all the time just to ensure capacity on a seasonal or periodic basis is not only unappealing, but unnecessary in the age of software-defined everything.

The problem is that scaling down is much, much harder than scaling up. Oh, not from the perspective of automation and orchestration. That is, as the kids say these days, easy peasy lemon squeezy. APIs have made the ability to add and remove resources simplicity itself. There isn't a load balancing service available today without this capability - at least not one that's worth having.

But if you peek behind the kimono, you're going to quickly find out that perhaps it isn't as easy peasy as it first appears. Scaling down requires a bit more finesse than scaling up, at least if you care about the end user experience.

Consider for a moment the process of scaling up (or out, as is more often the case). A certain threshold is reached that indicates a need for more capacity. More often than not this metric is based on connections, with each application instance able to handle an approximate number of connections. When that is reached, a new application instance (node) is launched, it's added to the load balanced pool, and voila! More capacity, more connections, more consumers.

awkward elasticity

At some point that same threshold is breached on the way back down. As capacity demand wanes, the total connection count (as measured by all connections across all instances) decreases. When that count crossed a pre-determined threshold, one instance is shut down, it's removed from the pool, and voila!

You've just disconnected a whole bunch of consumers - many of whom might have been in the middle of a transaction (you know, trying to give you money).

Needless to say, they aren't happy.

That's because many of the systems implementing elastic scale these days haven't been load balancing applications for nearly twenty years and didn't recognize the importance of graceful degradation, or quiescence.

Graceful degradation was used in the olden days (and still is today, to be fair) when initiating a maintenance cycle. The requirement was that a server (today an instance) needed to be shut down for maintenance but it could not disrupt current user sessions. The load balancer would be "told" to begin quiescing (or bleeding off) connections in preparation for downtime. The service would immediately stop sending new connections to that server (instance) while allowing existing connections to complete. In this way, consumers could complete their tasks and when no connections were left, the server would be shut down and maintenance could begin.

This is not a simple thing to achieve. The load balancing service must be intelligent enough to stop sending new connections to an instance but not interrupt existing connections. It must be able to manage both active and semi-active instances for the same application, which requires stateful management across all application instances.

In today's models, this means that elasticity must embrace a more graceful, elegant means of scaling down than just suddenly killing an instance and all its associated connections.

With more and more apps - both those aimed at employees and those designed for consumers - residing in cloud environments and managed service environments, it is critical to evaluate how such providers support elasticity. Methods that disrupt productivity or interrupt consumer transactions are hardly worth the few pennies saved by immediately shutting down an instance when a threshold is crossed.

It behooves emerging software-defined models and devops that plan on managing scale automatically to recognize that elasticity isn't just about responding to thresholds; it's about responding seamlessly - in both directions.

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.

@DevOpsSummit Stories
Founded in 1997, ActiveState is a global leader providing software application development and management solutions. The Company's products include: Stackato, a commercially supported Platform-as-a-Service (PaaS) that harnesses open source technologies such as Cloud Foundry and Docker; dynamic language distributions ActivePerl, ActivePython and ActiveTcl; and developer tools such as the popular Komodo Edit and Komodo IDE. Headquartered in Vancouver, Canada, ActiveState is trusted by customers an...
SYS-CON Events announced today that ElasticBox is holding a Hackathon at DevOps Summit, November 6 from 12 pm -4 pm at the Santa Clara Convention Center in Santa Clara, CA. You can enter as an individual or team of up to 10 developers. A New Star Is Born Every Month! All completed ElasticBoxes will then be sent to a judging panel - 12 winners will be featured on the ElasticBox website in 2015. All entrants will receive five full enterprise licenses for one year + ElasticBox headphones + Elasti...
SYS-CON Events announced today that Calm.io has been named “Bronze Sponsor” of DevOps Summit Silicon Valley, which will take place on November 4–6, 2014, at the Santa Clara Convention Center in Santa Clara, CA. Calm.io is a cloud orchestration platform for AWS, vCenter, OpenStack, or bare metal, that runs your CL tools puppet, Chef, shell, git, Jenkins, nagios, and will soon support New Relic and Docker. It can run hosted, or on premise and provides VM automation / expiry, self-service portals,...
Blue Box has closed a $10 million Series B financing. The round was led by a strategic investor and included participation from prior investors including Voyager Capital and Founders Collective, as well as the Blue Box executive team. This round follows a $4.3 million Series A closed in December of 2012 and led by Voyager Capital. In May of this year, the company announced general availability of its private cloud as a service offering, Blue Box Cloud. Since that release, the company has dem...
The speed of product development has increased massively in the past 10 years. At the same time our formal secure development and SDL methodologies have fallen behind. This forces product developers to choose between rapid release times and security. In his session at DevOps Summit, Michael Murray, Director of Cyber Security Consulting and Assessment at GE Healthcare, will examine the problems and present some solutions for moving security in to the DevOps lifecycle to ensure that we get fast A...
SYS-CON Events announced today that Zentera Systems, an industry visionary delivering hybrid-cloud management solutions, will exhibit at DevOps Summit Silicon Valley, which will take place on November 4–6, 2014, at the Santa Clara Convention Center in Santa Clara, CA. Zentera Systems, Inc.™ is a Silicon Valley based private company, providing a Cloud Federation Platform (CFP) built on a virtualization architecture with patent-pending technology to address virtual network, cloud firewall, data p...
Software development, like manufacturing, is a craft that requires the application of creative approaches to solve problems given a wide range of constraints. However, while engineering design may be craftwork, the production of most designed objects relies on a standardized and automated manufacturing process. By contrast, much of moving an application from prototype to production and, indeed, maintaining the application through its lifecycle has often remained craftwork. In his session at De...
High performing enterprise Software Quality Assurance (SQA) teams validate systems are ready for use – getting most actively involved as components integrate and form complete systems. These teams catch and report on defects, making sure the customer gets the best software possible. SQA teams have leveraged automation and virtualization to execute more thorough testing in less time – bringing Dev and Ops together, ensuring production readiness. Does the emergence of DevOps mean the end of Enterp...
In his keynote at DevOps Summit, David Tesar, Microsoft Technical Evangelist on Microsoft Azure and DevOps, will discuss how Microsoft teams who have made huge progress with a DevOps transformation effectively utilize operations staff and how challenges were overcome. Regardless of whether you are a startup or a mature enterprise, whether you are using PaaS, Micro Services, or Containerization, walk away with some practical tips where Ops can make a significant impact working with the developmen...
Cloudwick, the leading big data DevOps service and solution provider to the Fortune 1000, announced Big Loop, its multi-vendor operations platform. Cloudwick Big Loop creates greater collaboration between Fortune 1000 IT staff, developers and their database management systems as well as big data vendors. This allows customers to comprehensively manage and oversee their entire infrastructure, which leads to more successful production cluster operations, and scale-out. Cloudwick Big Loop supports ...

POMPTON LAKES, N.J., Oct. 17, 2014 /PRNewswire/ -- Kubisys announced today its namesake CID Platform, which automatically captures production environments and orchestrates the provisioning and deployment of replicas for development, testing and QA. The Kubisys CID Platform makes it easy for developers of mission critical multi-tier applications, such as Microsoft Dynamics AX, to follow DevOps practices for continuous delivery. The Oct. 20, 2014 04:00 PM EDT  Reads: 1,801

The recent trends like cloud computing, social, mobile and Internet of Things are forcing enterprises to modernize in order to compete in the competitive globalized markets. However, enterprises are approaching newer technologies with a more silo-ed way, gaining only sub optimal benefits. The Modern Enterprise model is presented as a newer way to think of enterprise IT, which takes a more holistic approach to embracing modern technologies. This model makes use of Composable Enterprise framework ...
Through the magic of cloud computing, infrastructure is no longer the long pole in the IT process. Organizations can now set up the infrastructure they require within minutes instead of weeks. However, removing this bottleneck has exposed another; application delivery is the next issue to be resolved. With the ongoing move to digital-first enterprises, companies are now faced with a software-intensive business environment. Simply put, IT needs to figure out how to accelerate the application depl...
There's fog coming to the world of IT. Some people are calling this "The Cloud." This fog turns everything inside out. It will take your monolithic applications, the guts of which are contained within large bodies of code, and break them apart so that discrete units of functionality are contained within their own process, exposed through an interface for others to see. Complexity is moving from the inside of a few large processes to the outside of many smaller processes. People are rightly sca...
This is part of the ever-expanding "Microservices and PaaS" blog series covering the rapidly evolving use of microservices in modern cloud software projects. Parts I and II introduced microservices concepts and discussed patterns and practices being spearheaded by microservices pioneers, notably Netflix, who were represented at a recent microservices meetup that was the genesis of this series. Part III presented a list of challenges and pitfalls that adopters of microservices face. This list is...
In their session at DevOps Summit, Stan Klimoff, CTO of Qubell, and Mike Becker, Senior Data Engineer for RingCentral, will share the lessons learned from implementing CI/CD pipeline on AWS for a customer analytics project powered by Cloudera Hadoop, HP Vertica and Tableau. Stan Klimoff is CTO of Qubell, the enterprise DevOps platform. Stan has more than a decade of experience building distributed systems for companies such as eBay, Cisco and Seagate. Qubell is helping enterprises to become mor...
The impact of DevOps in the cloud era is potentially profound. DevOps helps businesses deliver new features continuously, reduce cycle time and achieve sustained innovation by applying agile and lean principles to assist all stakeholders in an organization that develop, operate, or benefit from the business’ lifecycle. In his session at DevOps Summit, Prashanth Chandrasekar, General Manager at Rackspace, will exam whether / how companies can work with external DevOps specialists to achieve "De...
I just recently wrote a blog about BOTs causing unwanted traffic on our servers. Right after I wrote this blog I was notified about yet another “interesting” and unusual load behavior on our download page which is used by customers to download latest product versions and updates. If you see such a load behavior you typically assume that you just released a new product version or maybe an update to our agents and many people are downloading it like crazy. Unfortunately that was not the case. The...
SYS-CON Events announced today that O'Reilly Media has been named “Media 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. O'Reilly Media spreads the knowledge of innovators through its books, online services, magazines, and conferences. Since 1978, O'Reilly Media has been a chronicler and catalyst of cutting-edge development, homing in on the technology trends that really matter and spurri...
SYS-CON Events announced today that Gigaom Research has been named "Media 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. Ashar Baig, Research Director, Cloud, at Gigaom Research, will also lead a Power Panel on the topic "Choosing the Right Cloud Option." Gigaom Research provides timely, in-depth analysis of emerging technologies for individual and corporate subscribers. Gigaom Research'...