|By Rebecca Clinard||
|September 24, 2012 07:30 AM EDT||
The ability to conduct effective performance testing has become a highly desired skillset within the IT industry. Unfortunately, these highly sought-after skills are consistently in short supply. "Front-end testers" can work with a tool to create a realistic load and although this is an important skillset, creating the load is just the beginning of any performance project. Understanding the load patterns and tuning the environment makes the unique talents of a "performance engineer" worth their weight in gold.
Performance engineers require skills in data analysis such as resource usage patterns, modeling, capacity planning, and tuning in order to detect, isolate, and alleviate saturation points within a deployment. Performance testing generates concurrency conditions and exposes resource competition at a server level. When the competition results in a resource (such as a thread pool) becoming over-utilized, this resource becomes a bottleneck or a saturation point. Performance engineers need to first understand the underlying architectures and develop a sense of where to look for potential scalability issues. Much of these "senses" or skills come from experience, working in many multi-tier environments and successfully tuning bottlenecks. Here are some tips to make the challenging but rewarding transition from a front-end tester to a performance engineer.
Wisdom, Determination, Patience, and Communication
Who said there isn't a whole lot of psychology in technology? Whether you are determining the current capacity of a deployment or you are recreating a production problem, it's often a very complex task- so many moving parts within the infrastructure, so many numbers to analyze from so many sources, data sets of raw test results to turn into understandable formats, so many people to keep in the loop, so much technical coordination... I could go on and on. It's your professional soft skills which will keep you on the right course. It requires determination to unpeel the layers of an onion and investigate each tier of the deployment. It requires the wisdom to spot trends instead of pursuing the tangents of anomalies. It requires the dedication to keep an eye on many different metrics and isolate resource saturation. And it requires the patience to reproduce scenarios in order to make conclusions based on proof/evidence. And you need to accomplish all of this while being an excellent communicator!
Methodical Approach - The Constant
Spend your time wisely in the beginning and set up the most realistic test scenarios. Then "set" the performance scenario in stone. This means Do Not change even the most minute details in your test case: All transactions flows, all mixtures, all think times, all behaviors - no variations at this point. This is the "constant" in your experiment and it is the only way you can reproduce and compare results. Any deviation within the test case scenario will result in different throughputs which affect resource patterns. Not following this tip will surely lead you on a collision course with Analysis Paralysis!
Architectural Diagram - Identify Potential Bottlenecks by Visualization
Make sure you ask for and receive an architectural diagram of the entire deployment. Map out business transactions to resources utilized within the environment. Make sure you understand all the transaction flows, from front end load balancers down to the shared resource database. Study the deployment and hook up precise monitors, leaving no blind spots. Visualize where contentions or bottlenecks COULD occur. Each resource of the environment must be monitored for signs of saturation. In reality, it's in the identification of where to look for bottlenecks that is the more difficult task. Alleviating these bottlenecks is the easy (and most rewarding) part. But without an architectural map, your journey will easily end by the frustration of getting lost in the dark.
Tuning Hardware and Software Level Bottlenecks
"Tuning is an Art". "Tuning is a Science". Which is it? Hardware servers are restricted by the physical resources (disk io/memory, cpu). Software servers are much more configurable and this is where expertise in needed for tuning. Performance engineers must understand the workings of a "server" in thread pools, caching policies, memory allocations, connection pooling, etc. Tuning is a balancing act. It's the situation where you tune the software servers in order to take full advantage of hardware resources, without causing a flood. Simply opening up all the gates isn't going to help when the backend is saturated with requests. Tuning must be conservative, weighing all the benefits as well as the consequences.
Proof: Reproducible Results
Typically, a seasoned performance engineer will tune a layer of the environment only when the results are reproducible. Always use trends instead of points in time, mere spikes are not cause for architectural changes. As a rule of thumb, you should reproduce 3 times before you make a change. Sometimes this takes a while... So be prepared to be patient. For example, if you are emulating a production login rate of 3 users per second, but the performance deterioration doesn't occur until you have 2000 active users, it will take a while to see it. Making an unnecessary change simply muddies the waters, keep it clear and recreate those exact conditions.
Tune the First Occurring Bottleneck
Make sure you tune the layer which showed contention earliest in the performance test, not the first identified bottleneck. When monitoring a large complex system, there are many counters to keep in your sights. Don't jump the gun and tune a thread pool when you see it becomes saturated, this could actually be a symptom of the problem, not the root cause. Correlate (using graphing is easiest) the point of time of degradation of performance to the first saturation within the environment. Understandably, there is a ton of information to look at - keep it simpler by just looking at the free resources based on percentages (free threads, free cache, and free file descriptors) and this will allow you to spot a bottleneck quicker. When a free resource runs low, there's a possible bottleneck. Understand the resource utilization and free resources will allow you to understand a bottleneck before it affects the end-user response time. In other words, watch as the resource becomes utilized. When free gets low, keep it on your radar for a cause of performance degradation.
Iterative Tuning Process
Tuning is an iterative process. Know that once you have alleviated one bottleneck, you will surely encounter another one. But do not fret... All aspects of servers are limited and since nothing is infinite you will eventually reach the end. Tuning manipulates the gates, requests which don't have a resource are queued and must wait to be serviced. Tuning becomes a process you must repeat until the workload reaches target capacity with acceptable response times.
Validate, validate, validate. Just as important as recreating and tuning based upon proof is validating that the tuning change had the desired effect. Did it indeed impact scalability in a positive way? Often, performance engineers test out theories. And sometimes, the validation stage will cause a change to be reverted. It's ok that not every change will make it to production. The key is to use a very scientific approach in which you prove the result as well as the requirement.
I hope you gleaned some pearls of wisdom.
Creating the load and emulating production workload is a means to end - you obviously need to create the load before you can capacity plan or understand the scalability of the deployment. But it is the skills in performance analysis that are most valuable. The performance engineer who walks into a project, takes the lead, wastes no time in learning the environment, creates and/or executes the realistic tests, identifies current capacity, isolates and alleviates bottlenecks, documents results, mentors the juniors, and clearly and effectively communicates with everyone from developers on up to the CIO/CTO's, is truly a GOLD MINE.
Becoming a true performance engineer is no easy task, but it's well worth the effort!
WebRTC has had a real tough three or four years, and so have those working with it. Only a few short years ago, the development world were excited about WebRTC and proclaiming how awesome it was. You might have played with the technology a couple of years ago, only to find the extra infrastructure requirements were painful to implement and poorly documented. This probably left a bitter taste in your mouth, especially when things went wrong.
Aug. 28, 2015 11:45 PM EDT Reads: 400
SYS-CON Events announced today that HPM Networks will exhibit at the 17th International Cloud Expo®, which will take place on November 3–5, 2015, at the Santa Clara Convention Center in Santa Clara, CA. For 20 years, HPM Networks has been integrating technology solutions that solve complex business challenges. HPM Networks has designed solutions for both SMB and enterprise customers throughout the San Francisco Bay Area.
Aug. 28, 2015 11:30 PM EDT Reads: 825
As more and more data is generated from a variety of connected devices, the need to get insights from this data and predict future behavior and trends is increasingly essential for businesses. Real-time stream processing is needed in a variety of different industries such as Manufacturing, Oil and Gas, Automobile, Finance, Online Retail, Smart Grids, and Healthcare. Azure Stream Analytics is a fully managed distributed stream computation service that provides low latency, scalable processing of streaming data in the cloud with an enterprise grade SLA. It features built-in integration with Azur...
Aug. 28, 2015 07:45 PM EDT Reads: 174
Too often with compelling new technologies market participants become overly enamored with that attractiveness of the technology and neglect underlying business drivers. This tendency, what some call the “newest shiny object syndrome,” is understandable given that virtually all of us are heavily engaged in technology. But it is also mistaken. Without concrete business cases driving its deployment, IoT, like many other technologies before it, will fade into obscurity.
Aug. 28, 2015 06:00 PM EDT Reads: 311
With the proliferation of connected devices underpinning new Internet of Things systems, Brandon Schulz, Director of Luxoft IoT – Retail, will be looking at the transformation of the retail customer experience in brick and mortar stores in his session at @ThingsExpo. Questions he will address include: Will beacons drop to the wayside like QR codes, or be a proximity-based profit driver? How will the customer experience change in stores of all types when everything can be instrumented and analyzed? As an area of investment, how might a retail company move towards an innovation methodolo...
Aug. 28, 2015 05:30 PM EDT Reads: 405
Consumer IoT applications provide data about the user that just doesn’t exist in traditional PC or mobile web applications. This rich data, or “context,” enables the highly personalized consumer experiences that characterize many consumer IoT apps. This same data is also providing brands with unprecedented insight into how their connected products are being used, while, at the same time, powering highly targeted engagement and marketing opportunities. In his session at @ThingsExpo, Nathan Treloar, President and COO of Bebaio, will explore examples of brands transforming their businesses by t...
Aug. 28, 2015 03:45 PM EDT Reads: 168
A producer of the first smartphones and tablets, presenter Lee M. Williams will talk about how he is now applying his experience in mobile technology to the design and development of the next generation of Environmental and Sustainability Services at ETwater. In his session at @ThingsExpo, Lee Williams, COO of ETwater, will talk about how he is now applying his experience in mobile technology to the design and development of the next generation of Environmental and Sustainability Services at ETwater.
Aug. 28, 2015 02:00 PM EDT
SYS-CON Events announced today that Micron Technology, Inc., a global leader in advanced semiconductor systems, will exhibit at the 17th International Cloud Expo®, which will take place on November 3–5, 2015, at the Santa Clara Convention Center in Santa Clara, CA. Micron’s broad portfolio of high-performance memory technologies – including DRAM, NAND and NOR Flash – is the basis for solid state drives, modules, multichip packages and other system solutions. Backed by more than 35 years of technology leadership, Micron's memory solutions enable the world's most innovative computing, consumer,...
Aug. 28, 2015 12:30 PM EDT Reads: 146
SYS-CON Events announced today that Pythian, a global IT services company specializing in helping companies leverage disruptive technologies to optimize revenue-generating systems, has been named “Bronze Sponsor” of SYS-CON's 17th Cloud Expo, which will take place on November 3–5, 2015, at the Santa Clara Convention Center in Santa Clara, CA. Founded in 1997, Pythian is a global IT services company that helps companies compete by adopting disruptive technologies such as cloud, Big Data, advanced analytics, and DevOps to advance innovation and increase agility. Specializing in designing, imple...
Aug. 28, 2015 12:00 PM EDT Reads: 198
While many app developers are comfortable building apps for the smartphone, there is a whole new world out there. In his session at @ThingsExpo, Narayan Sainaney, Co-founder and CTO of Mojio, will discuss how the business case for connected car apps is growing and, with open platform companies having already done the heavy lifting, there really is no barrier to entry.
Aug. 28, 2015 11:30 AM EDT
As more intelligent IoT applications shift into gear, they’re merging into the ever-increasing traffic flow of the Internet. It won’t be long before we experience bottlenecks, as IoT traffic peaks during rush hours. Organizations that are unprepared will find themselves by the side of the road unable to cross back into the fast lane. As billions of new devices begin to communicate and exchange data – will your infrastructure be scalable enough to handle this new interconnected world?
Aug. 28, 2015 10:00 AM EDT
Through WebRTC, audio and video communications are being embedded more easily than ever into applications, helping carriers, enterprises and independent software vendors deliver greater functionality to their end users. With today’s business world increasingly focused on outcomes, users’ growing calls for ease of use, and businesses craving smarter, tighter integration, what’s the next step in delivering a richer, more immersive experience? That richer, more fully integrated experience comes about through a Communications Platform as a Service which allows for messaging, screen sharing, video...
Aug. 28, 2015 07:30 AM EDT Reads: 558
SYS-CON Events announced today that IceWarp will exhibit at the 17th International Cloud Expo®, which will take place on November 3–5, 2015, at the Santa Clara Convention Center in Santa Clara, CA. IceWarp, the leader of cloud and on-premise messaging, delivers secured email, chat, documents, conferencing and collaboration to today's mobile workforce, all in one unified interface
Aug. 28, 2015 03:00 AM EDT Reads: 357
The Internet of Things (IoT) is about the digitization of physical assets including sensors, devices, machines, gateways, and the network. It creates possibilities for significant value creation and new revenue generating business models via data democratization and ubiquitous analytics across IoT networks. The explosion of data in all forms in IoT requires a more robust and broader lens in order to enable smarter timely actions and better outcomes. Business operations become the key driver of IoT applications and projects. Business operations, IT, and data scientists need advanced analytics t...
Aug. 28, 2015 12:30 AM EDT Reads: 353
Akana has announced the availability of the new Akana Healthcare Solution. The API-driven solution helps healthcare organizations accelerate their transition to being secure, digitally interoperable businesses. It leverages the Health Level Seven International Fast Healthcare Interoperability Resources (HL7 FHIR) standard to enable broader business use of medical data. Akana developed the Healthcare Solution in response to healthcare businesses that want to increase electronic, multi-device access to health records while reducing operating costs and complying with government regulations.
Aug. 26, 2015 07:00 AM EDT Reads: 107
For IoT to grow as quickly as analyst firms’ project, a lot is going to fall on developers to quickly bring applications to market. But the lack of a standard development platform threatens to slow growth and make application development more time consuming and costly, much like we’ve seen in the mobile space. In his session at @ThingsExpo, Mike Weiner, Product Manager of the Omega DevCloud with KORE Telematics Inc., discussed the evolving requirements for developers as IoT matures and conducted a live demonstration of how quickly application development can happen when the need to comply wit...
Aug. 2, 2015 11:15 AM EDT Reads: 543
The Internet of Everything (IoE) brings together people, process, data and things to make networked connections more relevant and valuable than ever before – transforming information into knowledge and knowledge into wisdom. IoE creates new capabilities, richer experiences, and unprecedented opportunities to improve business and government operations, decision making and mission support capabilities.
Aug. 1, 2015 10:00 AM EDT Reads: 473
Explosive growth in connected devices. Enormous amounts of data for collection and analysis. Critical use of data for split-second decision making and actionable information. All three are factors in making the Internet of Things a reality. Yet, any one factor would have an IT organization pondering its infrastructure strategy. How should your organization enhance its IT framework to enable an Internet of Things implementation? In his session at @ThingsExpo, James Kirkland, Red Hat's Chief Architect for the Internet of Things and Intelligent Systems, described how to revolutionize your archit...
Jul. 30, 2015 07:30 PM EDT Reads: 1,561
MuleSoft has announced the findings of its 2015 Connectivity Benchmark Report on the adoption and business impact of APIs. The findings suggest traditional businesses are quickly evolving into "composable enterprises" built out of hundreds of connected software services, applications and devices. Most are embracing the Internet of Things (IoT) and microservices technologies like Docker. A majority are integrating wearables, like smart watches, and more than half plan to generate revenue with APIs within the next year.
Jul. 30, 2015 02:30 PM EDT Reads: 272
Growth hacking is common for startups to make unheard-of progress in building their business. Career Hacks can help Geek Girls and those who support them (yes, that's you too, Dad!) to excel in this typically male-dominated world. Get ready to learn the facts: Is there a bias against women in the tech / developer communities? Why are women 50% of the workforce, but hold only 24% of the STEM or IT positions? Some beginnings of what to do about it! In her Opening Keynote at 16th Cloud Expo, Sandy Carter, IBM General Manager Cloud Ecosystem and Developers, and a Social Business Evangelist, d...
Jul. 30, 2015 12:00 PM EDT Reads: 2,218