Welcome!

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

Related Topics: Machine Learning , Java IoT

Machine Learning : Article

Why You Can’t Compare Cross-Browser Execution Times of Selenium Tests

Cross-browser testing is different in Selenium

I am currently working on a blog where I am going to explain how to do cross-browser testing and performance analysis using dynaTrace. Before I am going to blog that How-To I want to share with you one thing that I have noticed when executing my tests in Internet Explorer 8 and Firefox 3.6. Test execution times are very different – but – this is not because one browser is slower than the other. It is because Selenium has different synchronization mechanisms in IE and FF to e.g: wait for a page to be loaded.

My Environment
I run a simple test on the latest 2.0 Beta build of Selenium. The test executes the following steps:

  • Opens the homepage of my test application
  • Enters username and password and hits the Submit Button
  • Then clicks through 3 different pages by clicking on standard links

Execution Times over Time
I executed this test multiple times. In every test iteration I first execute the test on Internet Explorer 8 and then on Firefox 3.6. I use dynaTrace AJAX Premium Extensions to track performance on all these test executions. Looking at the Test Automation View allows me to compare different metrics, over time and also across the two browsers. The following screenshot shows the execution time of the test scenario of the last 6 test iteration in both IE and FF. The green line represents IE with an execution time that is about 1.5s slower than FF.

Execution Time of this test is about 1.5 seconds slower on Internet Explorer than Firefox - but - it is not because IE is slower

Execution Time of this test is about 1.5 seconds slower on Internet Explorer than Firefox - but - it is not because IE is slower

So – looking at the execution time alone would let me assume that IE is just so much slower than Firefox. But – that is actually not the case.

Detailed Timeline Analysis
dynaTrace allows me to compare two tests. I can compare Network Downloads, Rendering Activity, JavaScript and DOM Executions or any Server-Side activity that these tests executed. The first view that I get to see is the Timeline Comparison. When we compare the test timeline of both tests we see this big gap in Internet Explorer where nothing really happens:

We can compare the test executed in IE with the one in FF side-by-side discovering this big time gap where Selenium just waits

We can compare the test executed in IE with the one in FF side-by-side discovering this big time gap where Selenium just waits

What this really tells us is that looking at execution times of tests is not good idea when we want to compare performance of tests across browsers. It seems Selenium has different ways to wait for certain events to happen. Depending on the browser this can have a significant impact on execution time.

Does this mean we can’t do performance tests with Selenium?

No – we can do performance tests – but – we need to look at different metrics. The dynaTrace AJAX Edition calculates a lot of KPIs such as Time Spent in JavaScript, Time Spent in Network Downloads, Number of Resources, Size of Resources, … – these are the metrics that are more interesting for us. With dynaTrace AJAX Premium I can also compare these results between browsers for my test. This is now showing me a much better picture – in fact – it seems the JavaScript code runs faster in IE than in FF:

It is important to compare other metrics than just overall test execution times when you want to compare cross browser performance

It is important to compare other metrics than just overall test execution times when you want to compare cross browser performance

Watch out for my How-To blog. In the meantime you can make yourself familiar with the free dynaTrace AJAX and the Premium Extensions.

 

Related reading:

  1. How to use your Selenium Tests for automated JavaScript/AJAX Performance Analysis With more than 3 million downloads, Selenium is the world’s...
  2. Antivirus Add-On for IE to cause 5 times slower page load times The dynaTrace AJAX Community has been really active lately –...
  3. dynaTrace AJAX Edition 3.0 released – FREE Next Generation Browser Diagnostics – PART I // With its latest release, dynaTrace updates its Product Suite...
  4. dynaTrace Firefox Closed Beta Program started We had quite a number of people showing interest in...
  5. Automate Cross-Browser Web 2.0 Performance Optimization: An E-Commerce Perspective This Wednesday, March 23rd at Noon ET / 9AM PT...

More Stories By Andreas Grabner

Andreas Grabner has been helping companies improve their application performance for 15+ years. He is a regular contributor within Web Performance and DevOps communities and a prolific speaker at user groups and conferences around the world. Reach him at @grabnerandi

@CloudExpo Stories
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...
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...
Most people haven’t heard the word, “gamification,” even though they probably, and perhaps unwittingly, participate in it every day. Gamification is “the process of adding games or game-like elements to something (as a task) so as to encourage participation.” Further, gamification is about bringing game mechanics – rules, constructs, processes, and methods – into the real world in an effort to engage people. In his session at @ThingsExpo, Robert Endo, owner and engagement manager of Intrepid D...
Recently, WebRTC has a lot of eyes from market. The use cases of WebRTC are expanding - video chat, online education, online health care etc. Not only for human-to-human communication, but also IoT use cases such as machine to human use cases can be seen recently. One of the typical use-case is remote camera monitoring. With WebRTC, people can have interoperability and flexibility for deploying monitoring service. However, the benefit of WebRTC for IoT is not only its convenience and interopera...
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...
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.
Companies are harnessing data in ways we once associated with science fiction. Analysts have access to a plethora of visualization and reporting tools, but considering the vast amount of data businesses collect and limitations of CPUs, end users are forced to design their structures and systems with limitations. Until now. As the cloud toolkit to analyze data has evolved, GPUs have stepped in to massively parallel SQL, visualization and machine learning.
"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.
"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.
"Venafi has a platform that allows you to manage, centralize and automate the complete life cycle of keys and certificates within the organization," explained Gina Osmond, Sr. Field Marketing Manager at Venafi, in this SYS-CON.tv interview at DevOps at 19th Cloud Expo, held November 1-3, 2016, at the Santa Clara Convention Center in Santa Clara, CA.
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...
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...
"We're developing a software that is based on the cloud environment and we are providing those services to corporations and the general public," explained Seungmin Kim, CEO/CTO of SM Systems Inc., 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.
Business professionals no longer wonder if they'll migrate to the cloud; it's now a matter of when. The cloud environment has proved to be a major force in transitioning to an agile business model that enables quick decisions and fast implementation that solidify customer relationships. And when the cloud is combined with the power of cognitive computing, it drives innovation and transformation that achieves astounding competitive advantage.
Leading companies, from the Global Fortune 500 to the smallest companies, are adopting hybrid cloud as the path to business advantage. Hybrid cloud depends on cloud services and on-premises infrastructure working in unison. Successful implementations require new levels of data mobility, enabled by an automated and seamless flow across on-premises and cloud resources. In his general session at 21st Cloud Expo, Greg Tevis, an IBM Storage Software Technical Strategist and Customer Solution Architec...
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...
To get the most out of their data, successful companies are not focusing on queries and data lakes, they are actively integrating analytics into their operations with a data-first application development approach. Real-time adjustments to improve revenues, reduce costs, or mitigate risk rely on applications that minimize latency on a variety of data sources. In his session at @BigDataExpo, Jack Norris, Senior Vice President, Data and Applications at MapR Technologies, reviewed best practices to ...
"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.
"Our strategy is to focus on the hyperscale providers - AWS, Azure, and Google. Over the last year we saw that a lot of developers need to learn how to do their job in the cloud and we see this DevOps movement that we are catering to with our content," stated Alessandro Fasan, Head of Global Sales at Cloud Academy, in this SYS-CON.tv interview at 20th Cloud Expo, held June 6-8, 2017, at the Javits Center in New York City, NY.
In his keynote at 19th Cloud Expo, Sheng Liang, co-founder and CEO of Rancher Labs, discussed the technological advances and new business opportunities created by the rapid adoption of containers. With the success of Amazon Web Services (AWS) and various open source technologies used to build private clouds, cloud computing has become an essential component of IT strategy. However, users continue to face challenges in implementing clouds, as older technologies evolve and newer ones like Docker c...