Welcome!

Server Monitoring Authors: Liz McMillan, Carmen Gonzalez, Ken Schwaber, JP Morgenthal, Pat Romanski

Related Topics: @DevOpsSummit, Microservices Expo, Linux Containers, Containers Expo Blog, Server Monitoring

@DevOpsSummit: Blog Feed Post

Configuration with #Jenkins | @DevOpsSummit #DevOps #APM #Monitoring

Configuration settings that are enabled during the application development are very useful

When Configuration Settings from Development Wreak Havoc in Production
By Asad Ali

As applications are promoted from the development environment to the CI or the QA environment and then into the production environment, it is very common for the configuration settings to be changed as the code is promoted. For example, the settings for the database connection pools are typically lower in development environment than the QA/Load Testing environment. The primary reason for the existence of the configuration setting differences is to enhance application performance. However, occasionally there are instances where the application code is mistakenly promoted into production without changing these settings. In such cases, such promotion of code can cause performance havoc in the production environment. This blog describes one such scenario.

During their proof of concept, a prospect requested we identify and resolve an issue that they were observing in the production environment. They had just promoted a newer version of their critical application to production and soon after the promotion of the code they stared to see significant increase in the response time when the end users tried to login to their web application. To diagnose the issue the prospect injected our agents into their production JVMs that were exhibiting the issue to the end user. With Dynatrace agents injected, we observed both high response time for login and that most of the time for the login request was spent in class loading.

Additionally, breakdown of the response time showed that most of the time for login web request was spent in synchronization (92%).

The response time breakdown of the login request clearly shows that 92% of the time is spent in synchronization.

The response time breakdown of the login request clearly shows that 92% of the time is spent in synchronization.

With the response time breakdown showing the highest amount of time in synchronization we took a thread dump on the JVM where the login request was being processed to get insight into thread locking issue. The thread dump showed 67 threads that were blocked in the JVM.

67 Threads were blocked on the JVM.

67 Threads were blocked on the JVM.

Locking Hotspots view shows the breakdown of the blocked threads

Locking Hotspots view shows the breakdown of the blocked threads

Further analysis of the content of the thread dump showed that most of the blocked threads were waiting for the resource (CompoundClassLoader) held by one running thread (Thread Id 5570678).

Thread Id 5570678 owned the monitor on which the other threads were blocked.

Thread Id 5570678 owned the monitor on which the other threads were blocked.

CompoundClassLoader is held by Thread 5570678.

CompoundClassLoader is held by Thread 5570678.

All blocked threads are waiting on CompoundClassLoader.

All blocked threads are waiting on CompoundClassLoader.

The thread stack trace for the running thread showed that it is trying to load the class from the file system. Examining the full trace of the thread dump shows that the threads on this JVM are creating a new facelet every time a web request is received.

getFacelet being called every time a request is processed by the thread.

getFacelet being called every time a request is processed by the thread.

While it is very normal for a JVM to spend some time to load classes when the JVM is initially started, it is NOT normal (or good for performance) for the class loading to continue even after the JVM has warmed up and most of the classes are already loaded.

The thread stack showed call to getFacelet(java.util.URL) method in the com.sun.facelets.impl.DefaultFaceletFactory class. Review of the source of this class showed that the method tries to load the class if the method needsToBeRefreshed() returns true.

Code snippet of com.sun.facelets.impl.DefaultFaceletFactory class.

Code snippet of com.sun.facelets.impl.DefaultFaceletFactory class.

And finally the code for needsToBeRefreshed() clearly shows that it returns true  if the refreshPeriod is set to 0.

needsToBeRefreshed() method shows that if the refresh period is set to 0, the class is refreshed every time.

needsToBeRefreshed() method shows that if the refresh period is set to 0, the class is refreshed every time.

The Facelets are capable of precompiling if you set javax.faces.FACELETS_REFRESH_PERIOD to -1. However, once set to -1, the JSF never re-compile/re-parses the Facelets files and holds the entire SAX-compiled/parsed XML tree.

Insert11

In the development process the REFRESH_PERIOD is typically set to 0 because it allows the developers to keep editing the Facelets file without the need to restart the server. What happened at this prospect is that the application code was promoted into production with the REFRESH_PERIOD is to 0 value and hence every time the user tried to login, the Facelets were forced to recompile and that in turn resulted in high response time.

Conclusion
Configuration settings that are enabled during the application development are very useful as they reduce the number of times the application server has to be started to test code changes. However, as this example shows, it is very important to disable development-level settings as the code moves out of the development environment because they can cause performance havoc in the production environment. One of the best practices to eliminate occurrences of such scenario is to make the configuration changes a part of the continuous integration tools like Jenkins.

The post When configuration settings from development wreak havoc in production appeared first on about:performance.

More Stories By APM Blog

APM: It’s all about application performance, scalability, and architecture: best practices, lifecycle and DevOps, mobile and web, enterprise, user experience

@ThingsExpo Stories
A strange thing is happening along the way to the Internet of Things, namely far too many devices to work with and manage. It has become clear that we'll need much higher efficiency user experiences that can allow us to more easily and scalably work with the thousands of devices that will soon be in each of our lives. Enter the conversational interface revolution, combining bots we can literally talk with, gesture to, and even direct with our thoughts, with embedded artificial intelligence, whic...
BnkToTheFuture.com is the largest online investment platform for investing in FinTech, Bitcoin and Blockchain companies. We believe the future of finance looks very different from the past and we aim to invest and provide trading opportunities for qualifying investors that want to build a portfolio in the sector in compliance with international financial regulations.
Imagine if you will, a retail floor so densely packed with sensors that they can pick up the movements of insects scurrying across a store aisle. Or a component of a piece of factory equipment so well-instrumented that its digital twin provides resolution down to the micrometer.
In his keynote at 18th Cloud Expo, Andrew Keys, Co-Founder of ConsenSys Enterprise, provided an overview of the evolution of the Internet and the Database and the future of their combination – the Blockchain. 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 settle...
Product connectivity goes hand and hand these days with increased use of personal data. New IoT devices are becoming more personalized than ever before. In his session at 22nd Cloud Expo | DXWorld Expo, Nicolas Fierro, CEO of MIMIR Blockchain Solutions, will discuss how in order to protect your data and privacy, IoT applications need to embrace Blockchain technology for a new level of product security never before seen - or needed.
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...
Nordstrom is transforming the way that they do business and the cloud is the key to enabling speed and hyper personalized customer experiences. In his session at 21st Cloud Expo, Ken Schow, VP of Engineering at Nordstrom, discussed some of the key learnings and common pitfalls of large enterprises moving to the cloud. This includes strategies around choosing a cloud provider(s), architecture, and lessons learned. In addition, he covered some of the best practices for structured team migration an...
No hype cycles or predictions of a gazillion things here. IoT is here. You get it. You know your business and have great ideas for a business transformation strategy. What comes next? Time to make it happen. In his session at @ThingsExpo, Jay Mason, an Associate Partner of Analytics, IoT & Cybersecurity at M&S Consulting, presented a step-by-step plan to develop your technology implementation strategy. He also discussed the evaluation of communication standards and IoT messaging protocols, data...
Coca-Cola’s Google powered digital signage system lays the groundwork for a more valuable connection between Coke and its customers. Digital signs pair software with high-resolution displays so that a message can be changed instantly based on what the operator wants to communicate or sell. In their Day 3 Keynote at 21st Cloud Expo, Greg Chambers, Global Group Director, Digital Innovation, Coca-Cola, and Vidya Nagarajan, a Senior Product Manager at Google, discussed how from store operations and ...
In his session at 21st Cloud Expo, Raju Shreewastava, founder of Big Data Trunk, provided a fun and simple way to introduce Machine Leaning to anyone and everyone. He solved a machine learning problem and demonstrated an easy way to be able to do machine learning without even coding. Raju Shreewastava is the founder of Big Data Trunk (www.BigDataTrunk.com), a Big Data Training and consulting firm with offices in the United States. He previously led the data warehouse/business intelligence and B...
"IBM is really all in on blockchain. We take a look at sort of the history of blockchain ledger technologies. It started out with bitcoin, Ethereum, and IBM evaluated these particular blockchain technologies and found they were anonymous and permissionless and that many companies were looking for permissioned blockchain," stated René Bostic, Technical VP of the IBM Cloud Unit in North America, in this SYS-CON.tv interview at 21st Cloud Expo, held Oct 31 – Nov 2, 2017, at the Santa Clara Conventi...
When shopping for a new data processing platform for IoT solutions, many development teams want to be able to test-drive options before making a choice. Yet when evaluating an IoT solution, it’s simply not feasible to do so at scale with physical devices. Building a sensor simulator is the next best choice; however, generating a realistic simulation at very high TPS with ease of configurability is a formidable challenge. When dealing with multiple application or transport protocols, you would be...
Smart cities have the potential to change our lives at so many levels for citizens: less pollution, reduced parking obstacles, better health, education and more energy savings. Real-time data streaming and the Internet of Things (IoT) possess the power to turn this vision into a reality. However, most organizations today are building their data infrastructure to focus solely on addressing immediate business needs vs. a platform capable of quickly adapting emerging technologies to address future ...
We are given a desktop platform with Java 8 or Java 9 installed and seek to find a way to deploy high-performance Java applications that use Java 3D and/or Jogl without having to run an installer. We are subject to the constraint that the applications be signed and deployed so that they can be run in a trusted environment (i.e., outside of the sandbox). Further, we seek to do this in a way that does not depend on bundling a JRE with our applications, as this makes downloads and installations rat...
Widespread fragmentation is stalling the growth of the IIoT and making it difficult for partners to work together. The number of software platforms, apps, hardware and connectivity standards is creating paralysis among businesses that are afraid of being locked into a solution. EdgeX Foundry is unifying the community around a common IoT edge framework and an ecosystem of interoperable components.
DX World EXPO, LLC, a Lighthouse Point, Florida-based startup trade show producer and the creator of "DXWorldEXPO® - Digital Transformation Conference & Expo" has announced its executive management team. The team is headed by Levent Selamoglu, who has been named CEO. "Now is the time for a truly global DX event, to bring together the leading minds from the technology world in a conversation about Digital Transformation," he said in making the announcement.
In this strange new world where more and more power is drawn from business technology, companies are effectively straddling two paths on the road to innovation and transformation into digital enterprises. The first path is the heritage trail – with “legacy” technology forming the background. Here, extant technologies are transformed by core IT teams to provide more API-driven approaches. Legacy systems can restrict companies that are transitioning into digital enterprises. To truly become a lead...
Digital Transformation (DX) is not a "one-size-fits all" strategy. Each organization needs to develop its own unique, long-term DX plan. It must do so by realizing that we now live in a data-driven age, and that technologies such as Cloud Computing, Big Data, the IoT, Cognitive Computing, and Blockchain are only tools. In her general session at 21st Cloud Expo, Rebecca Wanta explained how the strategy must focus on DX and include a commitment from top management to create great IT jobs, monitor ...
"Cloud Academy is an enterprise training platform for the cloud, specifically public clouds. We offer guided learning experiences on AWS, Azure, Google Cloud and all the surrounding methodologies and technologies that you need to know and your teams need to know in order to leverage the full benefits of the cloud," explained Alex Brower, VP of Marketing at Cloud Academy, in this SYS-CON.tv interview at 21st Cloud Expo, held Oct 31 – Nov 2, 2017, at the Santa Clara Convention Center in Santa Clar...
The IoT Will Grow: In what might be the most obvious prediction of the decade, the IoT will continue to expand next year, with more and more devices coming online every single day. What isn’t so obvious about this prediction: where that growth will occur. The retail, healthcare, and industrial/supply chain industries will likely see the greatest growth. Forrester Research has predicted the IoT will become “the backbone” of customer value as it continues to grow. It is no surprise that retail is ...