Click here to close now.

Welcome!

AJAX & REA Authors: Ian Goldsmith, Hovhannes Avoyan, Lori MacVittie, AppDynamics Blog, Liz McMillan

Related Topics: AJAX & REA, Java

AJAX & REA: Article

Best Practices on JavaScript and AJAX Performance

JavaScript can save your day or it can cause you nightmares

JavaScript can save your day or it can cause you nightmares. JavaScript and XHR (XmlHttpRequest) enable what the industry considers to be Web 2.0 – meaning highly interactive web sites where some application logic is pushed down to the client into the browsers JavaScript engine. As with any application code – regardless of the language and runtime environment – it is easy to not follow Best Practices which ultimately negatively impact the end-user experience with the site.

dynaTrace AJAX Edition has a unique capability to trace all JavaScript execution on the web page. It also traces calls into the Browser DOM (Document Object Model) and is able to capture method arguments and return values. The following illustration shows a JavaScript trace of a script execution in the PurePath view of the dynaTrace AJAX Edition

dynaTrace JavaScript PurePath showing full execution trace including calls into the DOM, method arguments and return values

dynaTrace JavaScript PurePath showing full execution trace including calls into the DOM, method arguments and return values

By getting this level of details on JavaScript execution it is easy to identify slow running JavaScript handlers, custom javascript code, slow access to the DOM and expensive or inefficient calls into 3rd party frameworks such as jQuery

In the Best Practices for JavaScript and AJAX Performance we list all common problems we have seen when working with our AJAX Edition users, people like Steve Souders or John Resig and our commercial customers over the last couple of months. It includes recommendations on how to avoid blocking script blocks, inefficient CSS Selectors with frameworks such as jQuery, reducing DOM manipulations and XHR calls. The latest beta version of the dynaTrace AJAX Edition implements some of these Best Practices to automatically analyze slow running JavaScript code.

Related Reading:

  1. Hands-On Guide: Verifying FIFA World Cup Web Site against Performance Best Practices Whether you call it Football, Futbol, Fussball, Futebol, Calcio or...
  2. Best Practices from Zappos to deliver WOW Performance Zappos - the leading eCommerce site for shoes and apparel –...
  3. Best Practices on Web Performance Optimization (WPO) Over the last couple of years performance of web applications...
  4. Week 8 – Challenges in Tracing JavaScript Performance by Example In an earlier post I already discussed several approaches towards...
  5. How to use your Selenium Tests for automated JavaScript/AJAX Performance Analysis With more than 3 million downloads, Selenium is the world’s...

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
There is no question that the cloud is where businesses want to host data. Until recently hypervisor virtualization was the most widely used method in cloud computing. Recently virtual containers have been gaining in popularity, and for good reason. In the debate between virtual machines and containers, the latter have been seen as the new kid on the block – and like other emerging technology have had some initial shortcomings. However, the container space has evolved drastically since coming on...
Discussions about cloud computing are evolving into discussions about enterprise IT in general. As enterprises increasingly migrate toward their own unique clouds, new issues such as the use of containers and microservices emerge to keep things interesting. In this Power Panel at 16th Cloud Expo, moderated by Conference Chair Roger Strukhoff, panelists will address the state of cloud computing today, and what enterprise IT professionals need to know about how the latest topics and trends affec...
T-Mobile has been transforming the wireless industry with its “Uncarrier” initiatives. Today as T-Mobile’s IT organization works to transform itself in a like manner, technical foundations built over the last couple of years are now key to their drive for more Agile delivery practices. In his session at DevOps Summit, Martin Krienke, Sr Development Manager at T-Mobile, will discuss where they started their Continuous Delivery journey, where they are today, and where they are going in an effort ...
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 ...
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...
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...
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.
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...
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 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...
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.
Today’s enterprise is being driven by disruptive competitive and human capital requirements to provide enterprise application access through not only desktops, but also mobile devices. To retrofit existing programs across all these devices using traditional programming methods is very costly and time consuming – often prohibitively so. In his session at @ThingsExpo, Jesse Shiah, CEO, President, and Co-Founder of AgilePoint Inc., discussed how you can create applications that run on all mobile ...
The OpenStack cloud operating system includes Trove, a database abstraction layer. Rather than applications connecting directly to a specific type of database, they connect to Trove, which in turn connects to one or more specific databases. One target database is Postgres Plus Cloud Database, which includes its own RESTful API. Trove was originally developed around MySQL, whose interfaces are significantly less complicated than those of the Postgres cloud database. In his session at 16th Cloud...
There are 182 billion emails sent every day, generating a lot of data about how recipients and ISPs respond. Many marketers take a more-is-better approach to stats, preferring to have the ability to slice and dice their email lists based numerous arbitrary stats. However, fundamentally what really matters is whether or not sending an email to a particular recipient will generate value. Data Scientists can design high-level insights such as engagement prediction models and content clusters that a...
It's time to face reality: "Americans are from Mars, Europeans are from Venus," and in today's increasingly connected world, understanding "inter-planetary" alignments and deviations is mission-critical for cloud. In her session at 15th Cloud Expo, Evelyn de Souza, Data Privacy and Compliance Strategy Leader at Cisco Systems, discussed cultural expectations of privacy based on new research across these elements
In today's application economy, enterprise organizations realize that it's their applications that are the heart and soul of their business. If their application users have a bad experience, their revenue and reputation are at stake. In his session at 15th Cloud Expo, Anand Akela, Senior Director of Product Marketing for Application Performance Management at CA Technologies, discussed how a user-centric Application Performance Management solution can help inspire your users with every applicati...
As enterprises engage with Big Data technologies to develop applications needed to meet operational demands, new computation fabrics are continually being introduced. To leverage these new innovations, organizations are sacrificing market opportunities to gain expertise in learning new systems. In his session at Big Data Expo, Supreet Oberoi, Vice President of Field Engineering at Concurrent, Inc., discussed how to leverage existing infrastructure and investments and future-proof them against e...
The consumption economy is here and so are cloud applications and solutions that offer more than subscription and flat fee models and at the same time are available on a pure consumption model, which not only reduces IT spend but also lowers infrastructure costs, and offers ease of use and availability. In their session at 15th Cloud Expo, Ermanno Bonifazi, CEO & Founder of Solgenia, and Ian Khan, Global Strategic Positioning & Brand Manager at Solgenia, discussed this shifting dynamic with an ...
Due of the rise of Hadoop, many enterprises are now deploying their first small clusters of 10 to 20 servers. At this small scale, the complexity of operating the cluster looks and feels like general data center servers. It is not until the clusters scale, as they inevitably do, when the pain caused by the exponential complexity becomes apparent. We've seen this problem occur time and time again. In his session at Big Data Expo, Greg Bruno, Vice President of Engineering and co-founder of StackI...
Once the decision has been made to move part or all of a workload to the cloud, a methodology for selecting that workload needs to be established. How do you move to the cloud? What does the discovery, assessment and planning look like? What workloads make sense? Which cloud model makes sense for each workload? What are the considerations for how to select the right cloud model? And how does that fit in with the overall IT transformation?