Click here to close now.

SYS-CON MEDIA Authors: Yeshim Deniz, Pat Romanski, Carmen Gonzalez, Liz McMillan, Roger Strukhoff

Related Topics: Cloud Expo, Java, Microservices Journal, Linux, SDN Journal, @DevOpsSummit

Cloud Expo: Article

How to Choose Where Your Load Should Come From

The goal of a load test is to replicate the traffic & conditions your app experiences in production as realistically as possible

The goal of a load test is to replicate the traffic & conditions your app experiences in production as realistically as possible

As a tester, you understand how important it is to create the most realistic load test possible to provide confidence that your web application won't fail in the field. But how do you know where your load should come from to produce realistic results?

In this article, we have outlined three options most organizations can choose from when determining where your load should come from.

  1. Generate load on dedicated infrastructure in the datacenter
  2. Generate load from a private cloud
  3. Generate load from distributed public cloud locations

There is a time and a place for all three of these options. In this post we will go over when you should do each test and why.

1. Generate load on dedicated infrastructure in the datacenter

When: Perform internal load generation for early stage performance tests and tests on internal IT apps that will be accessed by users behind your firewall.

Why: Load testing from dedicated infrastructure inside your own datacenter is the most common and typically the most accessible way to wring out performance issues in your applications. This type of testing should be performed as part of your regular testing process.

Essentially what happens is you define specific load and performance tests that push on the individual modules and user paths within the system, and make sure that no unintended bottlenecks were introduced during development. The kinds of issues you'll work out with this localized, constrained testing include:

  • Inadequate transaction design
  • Broken links
  • Poor configuration
  • Memory leaks
  • Unoptimized code
  • Sub-optimal session model
  • Ineffective caching
  • Database indexing, connection, and concurrency issues

While performing this type of load test on dedicated equipment is easy, there are a few issues with using this approach as your sole means of load testing - the first of which is that many companies simply do not have adequate dedicated infrastructure resources to realistically test application performance at scale. The capital expense involved with acquiring and managing network equipment, servers, and applications for the sole purpose of performance testing can be hard to justify - especially when you consider that this infrastructure may sit idle for a significant portion of its life.

Second, load testing from anywhere inside your own datacenter environment will test only application performance. It will not test the full capabilities of the datacenter (including network configurations, load balancing, or security systems) and therefore will not produce a realistic picture of the user experience.

Running load tests from your internal environment is an important part of improving application performance, but it is not sufficient. You should integrate tests like those outlined above as a frequent part of your build & integration process. As you near the end of a release cycle, you'll have confidence that the application's functionality performs well under periods of high traffic.

2. Generate load from within a private cloud

When: Perform tests from a private cloud when you need to ramp up your load generation infrastructure quickly for larger tests.

Why: To address some of the issues above, many organizations are running load tests from within their private clouds. Operating on this type of infrastructure has several benefits when compared with the first approach that has been outlined.

Functionally, this method of testing is best suited to the same types of performance tests that you would execute using dedicated hardware: database optimization, transaction design, and the rest. However, private clouds address some of the problems with running on dedicated hardware.

First, a private cloud can be significantly less expensive to operate, specifically because the cloud infrastructure can be leveraged across many different applications. When you are done with your load test, virtual machines can be reassigned to complete other tasks such as analytics, development, or other cloud-friendly business processes. This allows an IT organization to distribute infrastructure costs, thus lowering the overall expense.

Second, this approach lends itself very easily to more realistic scaling. You can grab more cycles and more disk space as needed, ultimately driving a more aggressive stress test of the application.

Chances are, however, since you are testing from within your own network and environment, you are still not stressing the complete datacenter. As a result, this type of load generation approach won't necessarily give you an accurate picture of what your users will experience in periods of high traffic.

3. Generate load from distributed public cloud locations

When: Perform this test for when your app will be accessed primarily from users outside your firewall from distributed locations.

Why: By running your load tests from outside the datacenter in a public cloud or even a remote private cloud environment, you will get a good picture of how your datacenter infrastructure handles high traffic. This third type of load will test a part of the application's delivery that no amount of testing from your own datacenter can duplicate. This includes:

  • Load balancers
  • Networking equipment configuration
  • Data center connectivity and bandwidth
  • Web firewalls and security systems
  • In-network caching and content distribution
  • Network architecture
  • DNS, web latency, network congestion

It's important to focus your testing so it puts the load in the right place. For example, load testing firewall or load-balancing infrastructure. You may even choose to load test multiple applications that exist within the same data center at the same time to see if it chokes up for any reason when the load is applied.

Another major point that many testers don't often consider is the fact users are accessing your app from many different regions across different service providers. To get a realistic picture of the actual user experience, it is important to see what their experience looks like from their access points anywhere in the world. This will give you a better understanding of what happens to your web application when users from different parts of the world are flooding your website with traffic.

Prevent a Disaster, Don't Cause One
The ultimate goal of a load test is to replicate the traffic and conditions your app experiences in production as realistically as possible to give you confidence that your site will not fail at peak times with actual live users. By looking at the three major options of where your load should come from, it will give you a better idea of how your app will perform under stress.

No matter what, each of these tests will catch something different in your application. And we all should know by now, if you catch a bug earlier in the process you won't have to pull out the big bucks to fix a major disaster down the road. Prevent a disaster, don't cause one.

More Stories By Tim Hinds

Tim Hinds is the Product Marketing Manager for NeoLoad at Neotys. He has a background in Agile software development, Scrum, Kanban, Continuous Integration, Continuous Delivery, and Continuous Testing practices.

Previously, Tim was Product Marketing Manager at AccuRev, a company acquired by Micro Focus, where he worked with software configuration management, issue tracking, Agile project management, continuous integration, workflow automation, and distributed version control systems.

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.


Latest Stories
Data-intensive companies that strive to gain insights from data using Big Data analytics tools can gain tremendous competitive advantage by deploying data-centric storage. Organizations generate large volumes of data, the vast majority of which is unstructured. As the volume and velocity of this unstructured data increases, the costs, risks and usability challenges associated with managing the unstructured data (regardless of file type, size or device) increases simultaneously, including end-to-...
Gartner predicts that the bulk of new IT spending by 2016 will be for cloud platforms and applications and that nearly half of large enterprises will have cloud deployments by the end of 2017. The benefits of the cloud may be clear for applications that can tolerate brief periods of downtime, but for critical applications like SQL Server, Oracle and SAP, companies need a strategy for HA and DR protection. While traditional SAN-based clusters are not possible in these environments, SANless cluste...
You often hear the two titles of "DevOps" and "Immutable Infrastructure" used independently. In his session at DevOps Summit, John Willis, Technical Evangelist for Docker, will cover the union between the two topics and why this is important. He will cover an overview of Immutable Infrastructure then show how an Immutable Continuous Delivery pipeline can be applied as a best practice for "DevOps." He will end the session with some interesting case study examples.
The 4th International Internet of @ThingsExpo, co-located with the 17th International Cloud Expo - to be held November 3-5, 2015, at the Santa Clara Convention Center in Santa Clara, CA - announces that its Call for Papers is open. The Internet of Things (IoT) is the biggest idea since the creation of the Worldwide Web more than 20 years ago.
SYS-CON Media named Andi Mann editor of DevOps Journal. DevOps Journal is focused on this critical enterprise IT topic in the world of cloud computing. DevOps Journal brings valuable information to DevOps professionals who are transforming the way enterprise IT is done. Andi Mann, Vice President, Strategic Solutions, at CA Technologies, is an accomplished digital business executive with extensive global expertise as a strategist, technologist, innovator, marketer, communicator, and thought lea...
Announced separately, New Relic is joining the Cloud Foundry Foundation to continue the support of customers and partners investing in this leading PaaS. As a member, New Relic is contributing the New Relic tile, service broker and build pack with the goal of easing the development of applications on Cloud Foundry and enabling the success of these applications without dedicated monitoring infrastructure. Supporting Quotes "The proliferation of microservices and new technologies like Docker ha...
Even though it’s now Microservices Journal, long-time fans of SOA World Magazine can take comfort in the fact that the URL – soa.sys-con.com – remains unchanged. And that’s no mistake, as microservices are really nothing more than a new and improved take on the Service-Oriented Architecture (SOA) best practices we struggled to hammer out over the last decade. Skeptics, however, might say that this change is nothing more than an exercise in buzzword-hopping. SOA is passé, and now that people are ...
The Domain Name Service (DNS) is one of the most important components in networking infrastructure, enabling users and services to access applications by translating URLs (names) into IP addresses (numbers). Because every icon and URL and all embedded content on a website requires a DNS lookup loading complex sites necessitates hundreds of DNS queries. In addition, as more internet-enabled ‘Things' get connected, people will rely on DNS to name and find their fridges, toasters and toilets. Acco...
There is little doubt that Big Data solutions will have an increasing role in the Enterprise IT mainstream over time. 8th International Big Data Expo, co-located with 17th International Cloud Expo - to be held November 3-5, 2015, at the Santa Clara Convention Center in Santa Clara, CA - has announced its Call for Papers is open. As advanced data storage, access and analytics technologies aimed at handling high-volume and/or fast moving data all move center stage, aided by the cloud computing bo...
The time is ripe for high speed resilient software defined storage solutions with unlimited scalability. ISS has been working with the leading open source projects and developed a commercial high performance solution that is able to grow forever without performance limitations. In his session at DevOps Summit, Alex Gorbachev, President of Intelligent Systems Services Inc., will share foundation principles of Ceph architecture, as well as the design to deliver this storage to traditional SAN st...
The 5th International DevOps Summit, co-located with 17th International Cloud Expo – being held November 3-5, 2015, at the Santa Clara Convention Center in Santa Clara, CA – announces that its Call for Papers is open. Born out of proven success in agile development, cloud computing, and process automation, DevOps is a macro trend you cannot afford to miss. From showcase success stories from early adopters and web-scale businesses, DevOps is expanding to organizations of all sizes, including the...
Enterprises are fast realizing the importance of integrating SaaS/Cloud applications, API and on-premises data and processes, to unleash hidden value. This webinar explores how managers can use a Microservice-centric approach to aggressively tackle the unexpected new integration challenges posed by proliferation of cloud, mobile, social and big data projects. Industry analyst and SOA expert Jason Bloomberg will strip away the hype from microservices, and clearly identify their advantages and d...
Since 2008 and for the first time in history, more than half of humans live in urban areas, urging cities to become “smart.” Today, cities can leverage the wide availability of smartphones combined with new technologies such as Beacons or NFC to connect their urban furniture and environment to create citizen-first services that improve transportation, way-finding and information delivery. In her session at @ThingsExpo, Laetitia Gazel-Anthoine, CEO of Connecthings, will focus on successful use c...
The Internet of Things promises to transform businesses (and lives), but navigating the business and technical path to success can be difficult to understand. In his session at @ThingsExpo, Sean Lorenz, Technical Product Manager for Xively at LogMeIn, demonstrated how to approach creating broadly successful connected customer solutions using real world business transformation studies including New England BioLabs and more.
Operational Hadoop and the Lambda Architecture for Streaming Data Apache Hadoop is emerging as a distributed platform for handling large and fast incoming streams of data. Predictive maintenance, supply chain optimization, and Internet-of-Things analysis are examples where Hadoop provides the scalable storage, processing, and analytics platform to gain meaningful insights from granular data that is typically only valuable from a large-scale, aggregate view. One architecture useful for capturing...