Welcome!

Machine Learning Authors: Liz McMillan, Pat Romanski, Elizabeth White, Yeshim Deniz, Corey Roth

Blog Feed Post

Load testing like a developer

Creating highly targeted load tests for your web server doesn’t have to be complicated. And it won’t be, at least not if you know what to look for.

The secret is to approach a load test with the mind of a developer. You’re not going to run a test just to punish your web server. You’re trying to gather valuable data that will aid you in keeping your web applications fast and responsive. To do this, let’s look at two simple steps to create a scientifically sound load test.

1. To plan your test, think like a user.
The first step is to outline exactly what type of web experience you’re testing for. Are you expecting users to log onto your site and remain for hours at a time? Or are a large number of users entering and leaving the site in short spurts? Or, are you expecting your about-to-be-released video to go viral, and you want to be sure your server can handle the load? No two websites are identical, and the same goes for the user experience on your site.

Let’s take a look at an example. An online shop might find it best to define the number of visits and purchases per hour that its servers must be able to handle. With this information, the shop can calculate it down to a value of each new visit and/or purchase per second. An example of this could be an hour-long test configured to send five new visitors to the site per second, simulate them surfing the product catalog, and have them start a new purchase every second.

2. Find the data that really matters.
Now that your load test is up and running, your next step is to comb through the mountain of incoming data to understand what’s happening on the server. During the load test for our hypothetical online shop, new simulated users are coming to the site and old simulated users are leaving the site. To judge the response time of the web server, we need to look at the number of parallel users. If the web server is slow, you’ll have a large number of virtual users, and if it’s fast, that number will be smaller.

When the results of a load test show unacceptable response times, it is often assumed that the network is the cause of the problem. In reality, this is seldom the case. Fortunately, it is quite easy to check this using test measurement data. Simply compare the response time for a static image (such as JPEG, GIF, or PNG) with the response time for a dynamically created HTML page of approximately the same size.

Consider this example:
A) The response time for a static GIF image of 200 kB is measured at 60 milliseconds.
B) The response time for a dynamically created HTML page with a size of 400 kB is measured at three seconds.

Assuming the response time of the static image depends solely on the network bandwidth (which is not always the case, but is useful for our purposes in this example), the dynamically created HTML page should have a response time of 120 milliseconds since it is only twice the size of the image. Since the actual response time of the HTML page is three seconds, the web application uses at least 2880 milliseconds (3000 minus 120) to produce and send the page.

However, one successful test does not guarantee a perfect application. You should be running load tests after any modification is made to the web server or application (i.e. new software release, upgrading database, etc.). These tests should run for at least 30 minutes, because often a web server does not crash instantly when it’s overloaded. Many can handle a large load for a few minutes, but might crash later after 15 or 20.

With these tips in mind, you’ll be on track to pinpointing your application’s performance issues. Perfection takes time, but as you tweak your tests to emulate your real-world traffic, your response times should gradually improve.

Read the original blog entry...

More Stories By Sven Hammar

Sven Hammar is Co-Founder and CEO of Apica. In 2005, he had the vision of starting a new SaaS company focused on application testing and performance. Today, that concept is Apica, the third IT company I’ve helped found in my career.

Before Apica, he co-founded and launched Celo Commuication, a security company built around PKI (e-ID) solutions. He served as CEO for three years and helped grow the company from five people to 85 people in two years. Right before co-founding Apica, he served as the Vice President of Marketing Bank and Finance at the security company Gemplus (GEMP).

Sven received his masters of science in industrial economics from the Institute of Technology (LitH) at Linköping University. When not working, you can find Sven golfing, working out, or with family and friends.

@CloudExpo Stories
Michael Maximilien, better known as max or Dr. Max, is a computer scientist with IBM. At IBM Research Triangle Park, he was a principal engineer for the worldwide industry point-of-sale standard: JavaPOS. At IBM Research, some highlights include pioneering research on semantic Web services, mashups, and cloud computing, and platform-as-a-service. He joined the IBM Cloud Labs in 2014 and works closely with Pivotal Inc., to help make the Cloud Found the best PaaS.
The “Digital Era” is forcing us to engage with new methods to build, operate and maintain applications. This transformation also implies an evolution to more and more intelligent applications to better engage with the customers, while creating significant market differentiators. In both cases, the cloud has become a key enabler to embrace this digital revolution. So, moving to the cloud is no longer the question; the new questions are HOW and WHEN. To make this equation even more complex, most ...
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...
As data explodes in quantity, importance and from new sources, the need for managing and protecting data residing across physical, virtual, and cloud environments grow with it. Managing data includes protecting it, indexing and classifying it for true, long-term management, compliance and E-Discovery. Commvault can ensure this with a single pane of glass solution – whether in a private cloud, a Service Provider delivered public cloud or a hybrid cloud environment – across the heterogeneous enter...
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...
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...
In a world where the internet rules all, where 94% of business buyers conduct online research, and where e-commerce sales are poised to fall between $427 billion and $443 billion by the end of this year, we think it's safe to say that your website is a vital part of your business strategy. Whether you're a B2B company, a local business, or an e-commerce site, digital presence is key to maintain in your drive towards success. Digital Performance will take priority in 2018 for the following reason...
Your homes and cars can be automated and self-serviced. Why can't your storage? From simply asking questions to analyze and troubleshoot your infrastructure, to provisioning storage with snapshots, recovery and replication, your wildest sci-fi dream has come true. In his session at @DevOpsSummit at 20th Cloud Expo, Dan Florea, Director of Product Management at Tintri, provided a ChatOps demo where you can talk to your storage and manage it from anywhere, through Slack and similar services with...
"This week we're really focusing on scalability, asset preservation and how do you back up to the cloud and in the cloud with object storage, which is really a new way of attacking dealing with your file, your blocked data, where you put it and how you access it," stated Jeff Greenwald, Senior Director of Market Development at HGST, in this SYS-CON.tv interview at 18th Cloud Expo, held June 7-9, 2016, at the Javits Center in New York City, NY.
Creating replica copies to tolerate a certain number of failures is easy, but very expensive at cloud-scale. Conventional RAID has lower overhead, but it is limited in the number of failures it can tolerate. And the management is like herding cats (overseeing capacity, rebuilds, migrations, and degraded performance). In his general session at 18th Cloud Expo, Scott Cleland, Senior Director of Product Marketing for the HGST Cloud Infrastructure Business Unit, discussed how a new approach is neces...
What's the role of an IT self-service portal when you get to continuous delivery and Infrastructure as Code? This general session showed how to create the continuous delivery culture and eight accelerators for leading the change. Don Demcsak is a DevOps and Cloud Native Modernization Principal for Dell EMC based out of New Jersey. He is a former, long time, Microsoft Most Valuable Professional, specializing in building and architecting Application Delivery Pipelines for hybrid legacy, and cloud ...
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...
"With Digital Experience Monitoring what used to be a simple visit to a web page has exploded into app on phones, data from social media feeds, competitive benchmarking - these are all components that are only available because of some type of digital asset," explained Leo Vasiliou, Director of Web Performance Engineering at Catchpoint Systems, in this SYS-CON.tv interview at DevOps Summit at 20th Cloud Expo, held June 6-8, 2017, at the Javits Center in New York City, NY.
"I focus on what we are calling CAST Highlight, which is our SaaS application portfolio analysis tool. It is an extremely lightweight tool that can integrate with pretty much any build process right now," explained Andrew Siegmund, Application Migration Specialist for CAST, 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.
"We view the cloud not as a specific technology but as a way of doing business and that way of doing business is transforming the way software, infrastructure and services are being delivered to business," explained Matthew Rosen, CEO and Director at Fusion, in this SYS-CON.tv interview at 18th Cloud Expo (http://www.CloudComputingExpo.com), held June 7-9 at the Javits Center in New York City, NY.
"We were founded in 2003 and the way we were founded was about good backup and good disaster recovery for our clients, and for the last 20 years we've been pretty consistent with that," noted Marc Malafronte, Territory Manager at StorageCraft, in this SYS-CON.tv interview at 20th Cloud Expo, held June 6-8, 2017, at the Javits Center in New York City, NY.
The Founder of NostaLab and a member of the Google Health Advisory Board, John is a unique combination of strategic thinker, marketer and entrepreneur. His career was built on the "science of advertising" combining strategy, creativity and marketing for industry-leading results. Combined with his ability to communicate complicated scientific concepts in a way that consumers and scientists alike can appreciate, John is a sought-after speaker for conferences on the forefront of healthcare science,...
WebRTC is great technology to build your own communication tools. It will be even more exciting experience it with advanced devices, such as a 360 Camera, 360 microphone, and a depth sensor camera. In his session at @ThingsExpo, Masashi Ganeko, a manager at INFOCOM Corporation, introduced two experimental projects from his team and what they learned from them. "Shotoku Tamago" uses the robot audition software HARK to track speakers in 360 video of a remote party. "Virtual Teleport" uses a multip...
"Software-defined storage is a big problem in this industry because so many people have different definitions as they see fit to use it," stated Peter McCallum, VP of Datacenter Solutions at FalconStor Software, in this SYS-CON.tv interview at 18th Cloud Expo, held June 7-9, 2016, at the Javits Center in New York City, NY.
Data is the fuel that drives the machine learning algorithmic engines and ultimately provides the business value. In his session at Cloud Expo, Ed Featherston, a director and senior enterprise architect at Collaborative Consulting, discussed the key considerations around quality, volume, timeliness, and pedigree that must be dealt with in order to properly fuel that engine.
In his session at Cloud Expo, Alan Winters, U.S. Head of Business Development at MobiDev, presented a success story of an entrepreneur who has both suffered through and benefited from offshore development across multiple businesses: The smart choice, or how to select the right offshore development partner Warning signs, or how to minimize chances of making the wrong choice Collaboration, or how to establish the most effective work processes Budget control, or how to maximize project result...