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Why Load Testing Is Important

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Why Load Testing Is Important

See why you should be load testing every time you commit to make sure you don't have memory leaks or other performance issues.

· Performance Zone ·
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As a developer or QA engineer, you probably incorporate many types of tests into your code checking: unit tests, integration tests, UI tests, and more. Occasionally, load tests might be overlooked in a sprint or release process. After all, if the system is working under functional testing, it's good to go, right? Wrong.

Here are 7 reasons you should be load testing every time you commit.

When testing your website, app or API endpoint under a load, you are actually simulating how it will perform when hundreds, thousands or millions of users visit it, in real life. Your system might perform completely differently for one user (functional testing) compared to many (load testing), due to the system's resources. So, to understand, analyze and fix errors, bugs, and bottlenecks before they actually happen, don't neglect the real people who will be using your system or product.

KPIs like response time, error rate, memory leakage, and CPU might be top-notch when running functional tests. But, when scaling to 1000s of users and running the tests from all over the globe, they could suddenly plummet and require dev attention. Load test to learn where and when your system breaks, fix the problems and avoid upset users and revenue loss. Incorporate different types of load when you're load testing, for example, sudden spikes, maintaining a super heavy load over time or gradual increase to expected loads, to learn how your system reacts to different traffic events.

Say you're a responsible developer, who actually did load test your system two months ago. The results showed that most of the API endpoints and services worked: some small bottlenecks were detected but you fixed them, ran the test again and saw that everything was performing well. Ever since you last tested, you probably released a few new versions, and for sure you made changes to your code.

All of these modifications might have affected your system in ways you don't know, due to dependencies, heisenbugs or other reasons. Your system's ability to handle a load could have also been affected. To make sure you're not surprised by a crash or slow responsiveness, run an automated load test every time you commit, as part of your continuous integration cycle.

Faster releases, lighter versions, and more automation create a better product and make for a better working environment for developers and engineers. Load testing is an inherent part of any continuous integration process, as part of all the tests that are run with every commit, alongside issue management, code analysis and more. So when you're setting up your automated continuous integration cycle with tools like open source Jenkins, add load testing to your workflow, with load testing tools like open source Apache JMeter™. If you need to test in the cloud, run your load tests with BlazeMeter.

Every time an important website crashes, headlines announce the blunder and angry users take to social media and condemn the website owners for not taking proper measures to avoid the crash. Unsatisfied customers have a good memory, and there is a limit to the number of times they will try to revisit a slow website or one that is down. Instead of dealing with frantic PR managers, desperately trying to get your website up under pressure and investing money in re-branding, just load test on time.

Teaching developers to load test and setting up automated load tests will take up some resources. But it will cost you more to constantly fix a website that crashed or to build up your brand reputation after scores of unhappy customers became fed up with your website moving too slow and moved on to your competitors. For example, one minute of downtime on Black Friday costs $4,700 on average. In addition, if your competitor's site crashes, and you did load test, you can seize the opportunity and get their users, thus increasing your revenues.

Events like Black Friday and Cyber Monday, big sports events, music festivals, etc. often include flash sales or mass-crowd interest, resulting in enormous traffic spikes. These types of events require special load testing, in addition to the daily load testing you are conducting. First, because these are irregular traffic patterns that you need to understand how your system is reacting to. Second, the mass audience deserves good service and can bring in very high revenue, so you should be doing everything you can to make it happen.

Use SaaS-based BlazeMeter to easily scale and run your load tests. Just upload your JMeter file, configure and run. Then, view real-time results in insightful graphs that can store data over time. BlazeMeter integrates with CI tools like Jenkins, TeamCity, and Bamboo.

So start testing now.

load testing ,performance testing ,apache jmeter ,api testing ,jmeter ,performance

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