Basics of load testing in Enterprise Applications using J-Meter

We need to test websites and applications for performance standards before delivering them to the client. The performance or benchmark testing is an ongoing function of software quality assurance that extends throughout the life cycle of the project. To build standards into the architecture of a system — the stability and response time of an application is extensively tested by applying a load or stress to the system.

Essentially, ‘load’ means the number of users using the application while ‘stability’ refers to the system’s ability to withstand the load created by the intended number of users. ‘Response time’ indicates the time taken to send a request, run the program and receive a response from a server.

Load testing on applications can be a challenging ordeal if a performance testing strategy is not predetermined. Testing tasks require multifaceted skill-sets — from writing test scripts, monitoring and analyzing test results to tweaking custom codes and scripts, and developing automated test scenarios for the actual testing.

So, is load testing on applications really necessary?

Quality testing ensures that the system is reliable, built for capacity and scalable. To achieve this, the involved stakeholders decide the budget considering its business impact.

Now, this raises a question — how do we predict traffic based on past trends? and how can we make the system more efficient to handle traffic without any dropouts? Also, if and when we hit peak loads, then how are we going to address the additional volume? For this, it is crucial to outline the performance testing strategy beforehand.

5 Key Benefits of Performance Testing

It identifies the issues at the early stage before they become too costly to resolve (for example, exposing bugs that do not surface in cursory testing, such as memory management bugs, memory leaks, buffer overflows, etc.).
Performance testing reduces development cycles, produces better quality and more scalable code.
It prevents revenue and credibility loss due to poor web site performance.
To enable intelligent planning for future scaling.
It ensures that the system meets performance expectations (response time, throughput, etc.) under-designed levels of load.

Organizations don’t prefer manual testing these days because it is expensive and requires human resources and hardware. It is also quite complex to coordinate and synchronize multiple testers. Also, repeatability is limited in manual testing.

To find the stability and response time of each API, we can test different scenarios by varying the load at different time intervals on the application. We can then automate the application by using any performance testing tool.

Performance Testing Tools

There are a bunch of different tools available for testers such as Open Source testing Tools — Open STA Diesel Test, TestMaker, Grinder, LoadSim, J-Meter, Rubis; Commercial testing tools— LoadRunner, Silk Performer, Qengine, Empirix e-Load.

Among these, the most commonly used tool is Apache J-Meter. It is a 100% Java desktop application with a graphical interface that uses the Swing graphical API. It can, therefore, run on any environment/workstation that accepts Java virtual machine, for example, Windows, Linux, Mac, etc.

We can automate testing the application by integrating the ‘selenium scripts’ in the J-Meter tool. (The software that can perform load tests, performance-functional tests, regression tests, etc. on different technologies.)

If the project is large in scope and the number of users keeps increasing day-by-day then the server’s load will be greater. In such situations, Performance testing is useful to identify at what point the application will crash. To find the number of errors and warnings in the code, we use the J-Meter tool.

How J-Meter Works

J-Meter simulates a group of users sending requests to a target server and returns statistics that show the performance/functionality of the target server/application via tables, graphs, etc.

The following figure illustrates how J-Meter works:

How J-Meter works - Load Testing on applications

The J-Meter performance testing tool can find the performance of any application (no matter whatever the language used to build the project).

First, it requires a test plan which describes a series of steps that the J-Meter will execute when run. A complete test plan will consist of one or more thread groups, samplers, logic controllers, listeners, timers, assertions and configuration elements.

The ‘thread’ group elements are the beginning of any test plan. Thread group element controls the number of threads J-Meter will use during the test run. We can also control the following via thread group: setting the number of threads, setting the ramp-up time and setting the loop count. The number of threads implies the number of users to the server application, while the ramp-up period defines the time taken by J-Meter to get all the threads running. Loop count identifies the number of times to execute the test.

After creating the ‘thread’ group, we need to define the number of users, iterations and ramp-up time (or usage time). We can create virtual servers depending on the number of users defined in the thread group and start performing the action based on the parameters defined. Internally J-Meter will record all the results like response code, response time, throughput, latency, etc. It produces the results in the form of graphs, trees and tables.

J-Meter has two types of controllers: Samplers and Logic controllers. Samplers allow the J-Meter to send specific requests to a server, while Logic controllers control the order of processing of samplers in a thread. They can change the order of requests coming from any of their child elements. Listeners are then used to view the results of samplers in the form of reporting tables, graphs, trees or simple text in some log files.

Please remember, always do performance testing by changing one parameter at a time. This way, you’ll be able to monitor response and throughput metrics and correct discrepancies accordingly. The real purpose of load testing is to ensure that the application or site is functional for businesses to deliver real value to their users — so test practically, and think like a real user.

If you’ve any queries or doubts, please feel free to write to hello@mantralabsglobal.com.

About the author: Syed Khalid Hussain is a Software Engineer-QA at Mantra Labs Pvt Ltd. He is a pro at different QA testing methodologies and is integral to the organization’s testing services.

Load Testing on Applications FAQs

What is the purpose of load testing?

Load testing is done to ensure that the application is capable of withstanding the load created by the intended number of users (web traffic).

Which tool is used for load testing?

There are open source and commercial tools available for load testing.
Open Source Tools are — Open STA Diesel Test, TestMaker, Grinder, LoadSim, J-Meter, Rubis. Commercial testing tools are — LoadRunner, Silk Performer, Qengine, Empirix e-Load.

How load testing is done?

Load testing is done using test scripts, monitoring and analyzing test results and developing automated test scenarios.

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In the world of product design, consistency is the cornerstone of delivering a seamless user experience. As digital products evolve and scale, the challenge of maintaining design consistency across multiple platforms, teams, and touchpoints becomes more complex. This is where design systems come in. A design system is a comprehensive set of guidelines, components, and tools that help designers and developers create a consistent and cohesive user interface (UI) and user experience (UX). From a designer’s perspective, building and maintaining a design system requires a strategic approach to ensure scalability, flexibility, and alignment with business goals.

Source: https://www.toptal.com/designers/ux/design-system)

Why Design Systems Matter?

Design systems are more than just style guides or pattern libraries. They offer a unified language for design and development, bridging the gap between creativity and functionality. Here are a few reasons why they are critical:

Consistency Across Products

One of the primary goals of a design system is to ensure uniformity across different platforms and devices. When users interact with a product, whether on a website or a mobile app, they expect a consistent experience. A well-implemented design system ensures that visual elements, interactions, and behaviors are aligned, offering a familiar and intuitive experience for users.

2. Faster Iteration

With a design system in place, teams can reuse components and patterns rather than reinventing the wheel for each new feature. This speeds up the design and development process, allowing teams to focus on solving new problems instead of reworking existing designs. For designers, it means less time spent on repetitive tasks and more time dedicated to innovation.

3. Scalability

As products grow and new features are added, maintaining a coherent UI/UX without a design system can become chaotic. A design system provides a scalable framework, enabling teams to add new elements or modules without compromising the overall consistency of the product.

4. Improved Collaboration

A design system fosters collaboration between designers, developers, and other stakeholders by providing a shared language and reference point. This ensures that design decisions are communicated effectively, reducing friction and misunderstandings between teams.

Building a Design System: A Designer’s Perspective

Designing a system from scratch can seem like a daunting task, but with a clear roadmap and understanding of core principles, it becomes a powerful tool for creating scalable and user-centered products.

1. Define the Core Principles

Before diving into visual components, it’s essential to establish the core principles of your design system. These principles serve as the foundation and guide decision-making throughout the process. Ask yourself:

• What are the key values of your brand?

• How should the design reflect the needs and emotions of users?

• What goals are you trying to achieve with your design system (e.g., accessibility, flexibility, innovation)?

For instance, if accessibility is a top priority, you’ll need to ensure that your design system accommodates users with different abilities, by providing color contrast guidelines, clear typographic hierarchies, and accessible components.

2. Create a Unified Visual Language

Once the principles are established, the next step is creating a cohesive visual language. This includes defining elements such as:

• Color Palette: A well-structured color palette ensures harmony across different UI components. It’s crucial to include primary, secondary, and accent colors, along with usage guidelines to avoid inconsistency.

• Typography: Define a typography system that establishes hierarchies and clarity, including font styles, sizes, line heights, and spacing. Consistent typography helps users navigate content effortlessly.

• Spacing and Grids: An established grid system ensures a balanced layout and harmony between different UI elements. Proper spacing guidelines prevent crowded or misaligned components.

• Iconography and Illustrations: Design guidelines for icons and illustrations help maintain visual consistency. Icons should follow a standard style (outlined, filled) and size, ensuring they align with the overall visual language.

Iconography and Illustrations: Design guidelines for icons and illustrations help maintain visual consistency. Icons should follow a standard style (outlined, filled) and size, ensuring they align with the overall visual language.

Image Source: https://designerup.co/blog/10-best-design-systems-and-how-to-learn-and-steal-from-them/)

3. Design Reusable Components

A design system is incomplete without reusable UI components. These components include buttons, forms, modals, and navigation elements that can be used across various features and pages. Each component should be:

• Modular: Components should be flexible and adaptable for different contexts. For example, a button should have variations for different states (hover, active, disabled) and types (primary, secondary, destructive).

• Documented: Each component needs comprehensive documentation that explains how it should be used, its variants, and the rules governing its application. This ensures consistency when different team members use the same component.

4. Implement Accessibility Guidelines

Accessibility should be at the forefront of every design system. As a designer, consider:

• Color Contrast: Ensure sufficient contrast between text and background for readability.

• Keyboard Navigation: Ensure that interactive components are navigable via keyboard for users who rely on keyboard shortcuts.

• Responsive Design: Components should be responsive, adapting seamlessly across different screen sizes and devices.

• Assistive Technologies: Design components should be compatible with screen readers and other assistive technologies to provide an inclusive experience.

Maintaining a Design System: Evolving with the Product

Once a design system is in place, the work doesn’t stop there. Maintaining it requires ongoing effort as the product evolves and new design challenges emerge. Here’s how designers can ensure the design system remains relevant and effective:

1. Regular Audits and Updates

A design system should be treated as a living document that evolves with the product. Regular audits are necessary to identify outdated or unused components. Designers should collaborate with developers to ensure new features are aligned with the existing design system, and updates should be documented to avoid fragmentation.

2. Version Control and Documentation

Version control is essential for keeping track of changes in the design system. Documenting why and how changes are made ensures that the design system grows in an organized manner. It also helps onboard new team members quickly, as they can reference updated guidelines.

3. Foster Collaboration Across Teams

Designers need to maintain an open line of communication with developers and other teams using the design system. Tools like Figma, Sketch, and Zeplin allow designers to share components and guidelines in real-time, fostering collaboration and ensuring that everyone is aligned.

Some well-known examples of design systems that have set benchmarks in the industry:

1. Google Material Design

URL: Material Design
Overview: Google’s Material Design is one of the most comprehensive design systems available. It provides guidelines on how to create visual, motion, and interaction design across platforms and devices. Material Design is known for its grid-based layouts, responsive animations, and depth effects like shadows and lighting.
Features:
- Comprehensive color palettes, typography, and iconography.
- Extensive component library (buttons, cards, etc.).
- Customizable UI components for both web and mobile applications.

2. Salesforce Lightning Design System

URL: Salesforce Lightning
Overview: Salesforce’s Lightning Design System provides a comprehensive library of UI components and resources to help build applications on the Salesforce platform. It ensures a consistent experience across Salesforce products and enables developers to create custom apps easily.
Features:
- Ready-to-use components, design tokens, and code snippets.
- Comprehensive accessibility guidelines to ensure inclusivity.
- Detailed documentation for developers to integrate components into Salesforce applications.

3. Microsoft Fluent Design System

URL: Fluent Design
Overview: Fluent Design is Microsoft’s design system, created to provide an engaging and scalable UI across all Microsoft products. It is heavily focused on interaction, animation, and motion while ensuring accessibility across various device ecosystems.
Features:
- Focus on depth, motion, and light to create modern and interactive UIs.
- Cross-platform components supporting web, desktop, and mobile applications.
- Accessible components with detailed guidelines for developers.

Conclusion

Building and maintaining a design system is an investment that pays off in the long run. It ensures consistency across your product, improves collaboration between teams, and allows for faster iteration and scalability. For designers, a design system is more than a collection of reusable components — it’s a framework that enables you to create user-centric products with confidence and clarity. By embracing modularity, documentation, and accessibility, you’ll ensure that your design system remains a valuable asset as your product grows.

About the Author:

Shristi is a creative professional with a passion for visual storytelling. She recently transitioned from the world of video and motion graphics to the exciting field of product design at Mantra Labs. When she’s not designing, she enjoys watching movies, traveling, and sharing her experiences through vlogs.

Basics of load testing in Enterprise Applications using J-Meter

So, is load testing on applications really necessary?

5 Key Benefits of Performance Testing