Concurrency Testing In Software Testing- Overview

September 7, 2023Kiruthika Devaraj
Concurrency Testing In Software Testing- Overview

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I bet you’ve been there when an app gives up on you and freezes because too many people use it simultaneously. It’s annoying, but it’s just one of those things that happen to all of us from time to time. That’s why software developers must perform concurrency testing, which assesses an application’s ability to handle multiple requests simultaneously. 

Testers can ensure that their software meets users’ expected high-performance standards by identifying and resolving issues related to race conditions, deadlocks, and other concurrency-related problems. 

Hey, if you’re a software tester, pay attention to the significance of concurrency testing. It’s essential for ensuring that your apps are top-notch in quality.

What is Concurrency Testing?

Concurrency testing is software testing that aims to identify and resolve issues that may arise when multiple users or processes access a system simultaneously. It helps ensure the system can handle concurrent requests without crashing or causing data corruption.

Why concurrency testing?

  • It is essential to conduct concurrency testing to ensure a system can handle multiple user requests. 
  • It can also help testers know the processes simultaneously without encountering crashes or data corruption.
  • It can detect and address potential issues early.
  • Concurrency testing can improve the system’s overall performance and reliability.

Advantages of Concurrent Testing

Check out the Advantages:

  • Faster testing process: Concurrent testing allows multiple tests to be executed simultaneously, reducing the overall time required for testing.
  • Increased test coverage: A more extensive range of scenarios and functionalities can be tested simultaneously by running multiple tests, improving test coverage.
  • Early defect detection: Concurrent testing helps identify defects and issues earlier in the development cycle, allowing for quicker resolution and preventing them from escalating into major problems.
  • Improved resource utilization: With concurrent testing, hardware, software, and test environments can be utilized more efficiently as multiple tests run concurrently on the same resources.
  • Enhanced scalability: Concurrent testing enables organizations to scale their efforts quickly by adding more parallel test executions without significantly impacting the testing time.
  • Better simulation of real-world scenarios: By executing multiple tests concurrently, it becomes easier to simulate real-world scenarios where different functionalities or components interact simultaneously.
  • Increased productivity: Concurrent testing reduces the waiting time between tests, enabling testers to work on other tasks while tests run.

Disadvantages of Concurrent Testing

Here are some disadvantages:

  • Increased complexity: Concurrent testing involves running multiple tests simultaneously, making the testing process more complex and challenging to manage.
  • Resource limitations: Concurrent testing requires a significant amount of resources, including hardware, software, and personnel. This can be a disadvantage for organizations with limited resources.
  • Difficulty isolating issues: When multiple tests are running concurrently, it can be challenging to isolate and identify the root cause of any issues. This can lead to longer debugging and troubleshooting times.
  • Increased risk of interference: Running multiple tests concurrently increases the risk of interference between different test cases. Interference can result in false positives or negatives, making it harder to assess the system’s quality under test accurately.
  • Lack of focus on individual tests: Individual test cases may need more attention or scrutiny with concurrent testing. This could lead to overlooking critical defects or vulnerabilities.
  • Limited test coverage:  This limited test coverage can leave potential issues undetected, posing a risk to the overall reliability and performance of the system.

Concurrent testing methods

Various methods are commonly employed for conducting concurrency testing. 

  1. One of the most popular and effective methods is known as Fuzz Testing. In this method, the tester deliberately inserts random, incorrect data into the system to observe how it responds. This approach can help detect and identify potential vulnerabilities in the design, which can then be addressed and rectified. 
  2. Another method that is frequently used is Random Testing. This involves running multiple threads simultaneously while randomizing the test inputs. This method can help detect race conditions and other issues that may arise when multiple lines access the same resources simultaneously.
  3. Code Review is another essential method that is often used in concurrency testing. In this approach, the testers thoroughly scrutinize the code and its structures to identify potential issues or weaknesses. This can help ensure the code is robust and reliable under high-load conditions. 
  4. Lastly, Static Analysis is a method that involves checking the coding system before the code is executed. This approach can help identify potential issues and vulnerabilities before they can cause any harm to the system. By combining these methods, testers can ensure the system is robust, reliable, and can handle high-load conditions without issues.

Automating concurrency testing 

Automation is key in today’s software development game, and concurrency testing isn’t different.

  1. Automating concurrency testing can be a game-changer in terms of efficiency.
  2. By automating these tests, you can save time and resources while ensuring your system functions as intended. 
  3. Plus, automation allows you to run tests more frequently, catching issues before they become bigger problems.
  4. Overall, automation is smart for anyone looking to streamline their testing process.

What tools to look for? 

When it comes to concurrency testing, there are several tools available that can help ensure the stability and reliability of concurrent systems. Here are some of the top tools worth considering:

  1. JMeter: JMeter is an open-source tool developed by the Apache Software Foundation. It is primarily used for load testing and performance measurement of web applications. However, it can also be utilized for concurrency testing. JMeter allows you to simulate multiple users accessing your application simultaneously, enabling you to analyze how well your system handles concurrent requests.
  2. LoadNinja: LoadNinja is a cloud-based tool focusing on ease of use and scalability. It allows you to record user interactions with your web application and replay them concurrently with thousands of virtual users. LoadNinja also provides detailed performance metrics and visualizations for analysis.
  3. WebLOAD: WebLOAD is a popular tool that offers robust load testing capabilities, including concurrency testing. It allows you to simulate thousands of virtual users and monitor system performance under heavy loads. It provides real-time analytics and customizable reports and supports protocols like HTTP, WebSocket, SOAP, etc.
  4. LoadView: LoadView is an open-source and complete solution designed to offer exceptional reliability and efficiency to performance engineers. With LoadView, you can rest assured that your system can handle even the most demanding traffic loads. As a fully managed, cloud-based solution, LoadView has a wide range of features that can help identify and address any issues that may arise during periods of high traffic.


Time to wrap up!

If you’re developing software, testing for concurrency is essential. This means ensuring your app or program can handle many people or processes simultaneously without any problems. Doing this can avoid issues like the app freezing or crashing when too many people use it. 

Testing for concurrency is a great way to ensure everyone has a good experience and keeps your customers happy.

Here is a blog that talks in detail about Visual Testing, a new launch in Testsigma. 

Know in detail: https://testsigma.com/blog/testsigma-announces-visual-testing/

Frequently Asked Questions

What is concurrent user testing?

Concurrent user testing is a software testing technique that evaluates the performance and functionality of an application when multiple users access it simultaneously. This type of testing is essential for applications that are expected to receive a high number of concurrent users, such as e-commerce platforms, social media networks, and online gaming websites.

What is parallel vs. concurrent testing?

Parallel testing refers to running multiple tests simultaneously on different environments or configurations to increase test coverage and reduce execution time. Concurrent testing, on the other hand, involves executing multiple tests simultaneously on the same environment or configuration, focusing on identifying issues related to resource contention and system performance. Both approaches aim to optimize testing efficiency but differ in focus and execution setup.

What is an example of concurrency testing?

An example of concurrency testing is testing an e-commerce website that processes multiple user requests simultaneously. This testing involves simulating high-traffic scenarios to determine if the website can handle the load without crashing or slowing down. The testing can also include checking whether the user data is stored correctly or the transactions are processed accurately.

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