@CloudExpo Authors: Elizabeth White, Yeshim Deniz, Liz McMillan, Pat Romanski, Gordon Haff

Related Topics: @CloudExpo, Java IoT, Microservices Expo, Microsoft Cloud, Containers Expo Blog, Apache

@CloudExpo: Blog Feed Post

Back to Basics: The Theory of (Performance) Relativity

Choice of load balancing algorithms is critical to ensuring consistent and acceptable performance

Choice of load balancing algorithms is critical to ensuring consistent and acceptable performance

One of the primary reasons folks use a Load balancer is scalability with a secondary driver of maintaining performance. We all know the data exists to prove that "seconds matter" and current users of the web have itchy fingers, ready to head for the competition the microsecond they experience any kind of delay.

Similarly, we know that productivity is inherently tied to performance. With more and more critical business functions "webified", the longer it takes to load a page the longer the delay a customer or help desk service representative experiences, reducing the number of calls or customers that can be serviced in any given measurable period.


So performance is paramount, I see no reason to persuade you further to come to that conclusion.

Ensuring performance then is a vital operational directive. One of the ways operations tries to meet that objective is through load balancing. Distributing load ensures available and can be used to offset any latency introduced by increasing capacity (again, I don't think there's anyone who'll argue against the premise that load and performance degradation are inherently tied together).

But just adding a load balancing service isn't enough. The algorithm used to distribute load will invariably impact performance – for better or for worse.

Consider the industry standard "fastest response time" algorithm. This algorithm distributes load based on the historical performance of each instance in the pool (farm). On the surface, this seems like a good choice. After all, what you want is the fastest response time, so why not base load balancing decisions on the metric against which you are going to be measured?

The answer is simple: "fastest" is relative. With very light load on a pool of, say, three servers, "fastest" might mean sub-second responses. But as load increases and performance decreases, "fastest" might start creeping up into the seconds – if not more. Sure, you're still automagically choosing the fastest of the three servers, but "fastest" is absolutely relative to the measurements of all three servers.

Thus, "fastest response time" is probably a poor choice if one of your goals is measured in response time to the ultimate customer – unless you combine it with an upper connection limit.


One of the negatives of adopting a cloud computing paradigm with a nearly religious-like zeal is that you buy into the notion that utilization is the most important metric in the data center. You simply do not want to be wasting CPU cycles, because that means you're inefficient and not leveraging cloud to its fullest potential.

Well, horse-puckey. The reality is that 100% utilization and consistently well-performing applications do not go hand in hand. Period. You can have one, but not the other. You're going to have to choose which is more important a measurement – fast applications or full utilization.

operational axiom 2

In the six years I spent load testing everything from web applications to web application firewalls to load balancers to XML gateways one axiom always, always, remained true:

As load increases performance decreases.

You're welcome to test and retest and retest again to prove that wrong, but good luck. I've never seen performance increase or even stay the same as utilization approaches 100%.

Now, once you accept that reality you can use it to your advantage. You know that performance is going to decrease as load increases, you just don't know at what point the degradation will become unacceptable to your users. So you need to test to find that breaking point. You want to stress the application and measure the degradation, noting the number of concurrent connections at which performance starts to degrade into unacceptable territory. That is your connection limit.

Keep track of that limit (for the application, specifically, because not all applications will have the same limits). When you configure your load balancing service you can now select fastest response time but you also need to input hard connection limits on a per-instance basis. This prevents each instance from passing through the load-performance confluence that causes end-users to start calling up the help desk or sighing "the computer is slow" while on the phone with their customers.

This means testing. Not once, not twice, but at least three runs. Make sure you've found the right load-performance confluence point and write it down. On your hand, in permanent marker.

While cloud computing and virtualization have certainly simplified load balancing services in terms of deployment, it's still up to you to figure out the right settings and configuration options to ensure that your applications are performing with the appropriate levels of "fast".

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.

@CloudExpo Stories
"NetApp is known as a data management leader but we do a lot more than just data management on-prem with the data centers of our customers. We're also big in the hybrid cloud," explained Wes Talbert, Principal Architect at NetApp, in this SYS-CON.tv interview at 21st Cloud Expo, held Oct 31 – Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA.
Andrew Keys is Co-Founder of ConsenSys Enterprise. He comes to ConsenSys Enterprise with capital markets, technology and entrepreneurial experience. Previously, he worked for UBS investment bank in equities analysis. Later, he was responsible for the creation and distribution of life settlement products to hedge funds and investment banks. After, he co-founded a revenue cycle management company where he learned about Bitcoin and eventually Ethereal. Andrew's role at ConsenSys Enterprise is a mul...
Evan Kirstel is an internationally recognized thought leader and social media influencer in IoT (#1 in 2017), Cloud, Data Security (2016), Health Tech (#9 in 2017), Digital Health (#6 in 2016), B2B Marketing (#5 in 2015), AI, Smart Home, Digital (2017), IIoT (#1 in 2017) and Telecom/Wireless/5G. His connections are a "Who's Who" in these technologies, He is in the top 10 most mentioned/re-tweeted by CMOs and CIOs (2016) and have been recently named 5th most influential B2B marketeer in the US. H...
The best way to leverage your Cloud Expo presence as a sponsor and exhibitor is to plan your news announcements around our events. The press covering Cloud Expo and @ThingsExpo will have access to these releases and will amplify your news announcements. More than two dozen Cloud companies either set deals at our shows or have announced their mergers and acquisitions at Cloud Expo. Product announcements during our show provide your company with the most reach through our targeted audiences.
DevOpsSummit New York 2018, colocated with CloudEXPO | DXWorldEXPO New York 2018 will be held November 11-13, 2018, in New York City. Digital Transformation (DX) is a major focus with the introduction of DXWorldEXPO within the program. Successful transformation requires a laser focus on being data-driven and on using all the tools available that enable transformation if they plan to survive over the long term. A total of 88% of Fortune 500 companies from a generation ago are now out of bus...
With 10 simultaneous tracks, keynotes, general sessions and targeted breakout classes, @CloudEXPO and DXWorldEXPO are two of the most important technology events of the year. Since its launch over eight years ago, @CloudEXPO and DXWorldEXPO have presented a rock star faculty as well as showcased hundreds of sponsors and exhibitors! In this blog post, we provide 7 tips on how, as part of our world-class faculty, you can deliver one of the most popular sessions at our events. But before reading...
DXWordEXPO New York 2018, colocated with CloudEXPO New York 2018 will be held November 11-13, 2018, in New York City and will bring together Cloud Computing, FinTech and Blockchain, Digital Transformation, Big Data, Internet of Things, DevOps, AI, Machine Learning and WebRTC to one location.
DXWorldEXPO LLC announced today that "Miami Blockchain Event by FinTechEXPO" has announced that its Call for Papers is now open. The two-day event will present 20 top Blockchain experts. All speaking inquiries which covers the following information can be submitted by email to [email protected] Financial enterprises in New York City, London, Singapore, and other world financial capitals are embracing a new generation of smart, automated FinTech that eliminates many cumbersome, slow, and expe...
As you move to the cloud, your network should be efficient, secure, and easy to manage. An enterprise adopting a hybrid or public cloud needs systems and tools that provide: Agility: ability to deliver applications and services faster, even in complex hybrid environments Easier manageability: enable reliable connectivity with complete oversight as the data center network evolves Greater efficiency: eliminate wasted effort while reducing errors and optimize asset utilization Security: implemen...
DXWorldEXPO | CloudEXPO are the world's most influential, independent events where Cloud Computing was coined and where technology buyers and vendors meet to experience and discuss the big picture of Digital Transformation and all of the strategies, tactics, and tools they need to realize their goals. Sponsors of DXWorldEXPO | CloudEXPO benefit from unmatched branding, profile building and lead generation opportunities.
@DevOpsSummit New York 2018, colocated with CloudEXPO | DXWorldEXPO New York 2018 will be held November 11-13, 2018, in New York City. From showcase success stories from early adopters and web-scale businesses, DevOps is expanding to organizations of all sizes, including the world's largest enterprises - and delivering real results.
With tough new regulations coming to Europe on data privacy in May 2018, Calligo will explain why in reality the effect is global and transforms how you consider critical data. EU GDPR fundamentally rewrites the rules for cloud, Big Data and IoT. In his session at 21st Cloud Expo, Adam Ryan, Vice President and General Manager EMEA at Calligo, examined the regulations and provided insight on how it affects technology, challenges the established rules and will usher in new levels of diligence arou...
Dion Hinchcliffe is an internationally recognized digital expert, bestselling book author, frequent keynote speaker, analyst, futurist, and transformation expert based in Washington, DC. He is currently Chief Strategy Officer at the industry-leading digital strategy and online community solutions firm, 7Summits.
"We started a Master of Science in business analytics - that's the hot topic. We serve the business community around San Francisco so we educate the working professionals and this is where they all want to be," explained Judy Lee, Associate Professor and Department Chair at Golden Gate University, in this SYS-CON.tv interview at 21st Cloud Expo, held Oct 31 – Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA.
DXWorldEXPO LLC announced today that Dez Blanchfield joined the faculty of CloudEXPO's "10-Year Anniversary Event" which will take place on November 11-13, 2018 in New York City. Dez is a strategic leader in business and digital transformation with 25 years of experience in the IT and telecommunications industries developing strategies and implementing business initiatives. He has a breadth of expertise spanning technologies such as cloud computing, big data and analytics, cognitive computing, m...
Digital Transformation and Disruption, Amazon Style - What You Can Learn. Chris Kocher is a co-founder of Grey Heron, a management and strategic marketing consulting firm. He has 25+ years in both strategic and hands-on operating experience helping executives and investors build revenues and shareholder value. He has consulted with over 130 companies on innovating with new business models, product strategies and monetization. Chris has held management positions at HP and Symantec in addition to ...
Cloud-enabled transformation has evolved from cost saving measure to business innovation strategy -- one that combines the cloud with cognitive capabilities to drive market disruption. Learn how you can achieve the insight and agility you need to gain a competitive advantage. Industry-acclaimed CTO and cloud expert, Shankar Kalyana presents. Only the most exceptional IBMers are appointed with the rare distinction of IBM Fellow, the highest technical honor in the company. Shankar has also receive...
There is a huge demand for responsive, real-time mobile and web experiences, but current architectural patterns do not easily accommodate applications that respond to events in real time. Common solutions using message queues or HTTP long-polling quickly lead to resiliency, scalability and development velocity challenges. In his session at 21st Cloud Expo, Ryland Degnan, a Senior Software Engineer on the Netflix Edge Platform team, will discuss how by leveraging a reactive stream-based protocol,...
Enterprises have taken advantage of IoT to achieve important revenue and cost advantages. What is less apparent is how incumbent enterprises operating at scale have, following success with IoT, built analytic, operations management and software development capabilities - ranging from autonomous vehicles to manageable robotics installations. They have embraced these capabilities as if they were Silicon Valley startups.
DXWorldEXPO LLC announced today that Kevin Jackson joined the faculty of CloudEXPO's "10-Year Anniversary Event" which will take place on November 11-13, 2018 in New York City. Kevin L. Jackson is a globally recognized cloud computing expert and Founder/Author of the award winning "Cloud Musings" blog. Mr. Jackson has also been recognized as a "Top 100 Cybersecurity Influencer and Brand" by Onalytica (2015), a Huffington Post "Top 100 Cloud Computing Experts on Twitter" (2013) and a "Top 50 C...