How do you test the performance of your web application portfolio with JavaScript?

Performance testing matters to to test web page behaviour on different scenerios as high traffic, low bandwidth. It allows to identify bottelnecks, bugs, and mistakes. It helps to decide how to optimize application.

Performance testing isn't an option; it's a necessity. It ensures your app can handle the heat of real-world usage, preventing crashes and slowdowns. It's the backbone of a seamless user experience and directly impacts customer satisfaction.

Performance testing is a fundamental part of the software development process that ensures web applications meet performance expectations, deliver a positive user experience, and operate reliably under various conditions. It is a proactive approach to identify and address performance issues before they impact users or business operations.

My view is that performance testing needs to be integrated into the application development process. For example, in the CI/CD process after new features have been deployed. It's useful to see that the performance of your application is still within reasonable limits, because if you lose attention and eventually see low performance in the final release, it's likely to be too late and very difficult to fix.

Performance testing is a critical aspect of the software development life cycle. 1) User Experience - Slow and poorly performing applications can frustrate users, leading to a negative user experience and potential abandonment of the application. 2) Customer Satisfaction - Users are more likely to engage with and return to applications that provide a smooth and responsive experience. 3) Business Reputation - Users are more likely to trust and recommend applications that perform well, contributing to positive brand perception 4) Cost Efficiency - Optimizing performance can lead to cost savings by reducing the need for additional server infrastructure and resources

To perform performance testing of a web application with JavaScript: -Define Performance Metrics: Decide on key indicators like load time, response time, and throughput. -Select Tools: Choose relevant tools like Lighthouse, JMeter, or WebPageTest for testing and analysis. -Develop Test Scenarios: Create scenarios that replicate user behavior and application usage patterns. -Simulate Various Environments: Test across different devices, browsers, and network conditions. -Automate Testing -Profile JavaScript Code -Conduct Load and Stress Testing -Optimize Based on Findings -Regular Testing

1. **Leverage Lighthouse:** Use Chrome's Lighthouse in DevTools for comprehensive audits and actionable suggestions. 2. **Performance API:** Measure intervals with `performance.now()` and analyze code blocks using `performance.mark()`. 3. **Monitoring Tools:** Employ `web-vitals` for vital metrics monitoring. 4. **Browser Profilers:** Use built-in browser profilers to spot and address performance bottlenecks. 5. **Load Testing:** Tools like `Artillery` simulate heavy traffic to assess scalability. 6. **Network Throttling:** DevTools' network throttling helps test different network speeds. 7. **Bundle Analysis:** `webpack-bundle-analyzer` aids in optimizing code splitting and load times.

Test Your Web App's Power with JavaScript: 1. Analyzes performance, accessibility, best practices, and SEO, giving you a complete picture with scores and reports. 3. Tests from multiple locations, browsers, and devices, providing detailed metrics on speed, paint times, and interactivity. 4. Simulates real user scenarios, generating load and measuring response time, throughput, errors, and more. 5. Create and run benchmarks for your JavaScript code, accurately gauging execution time, variance, and standard deviation.

I used to use Lighthouse and Core Web Vitals for it. Lighthouse driven approach can be used in the deployment pipelines such as the GitHub Actions or Bitbucket Pipelines.

Performance types are as below. 1) Load Testing To measure the time taken by a function to execute Two methods are: Using the performance. now() method. Using console. time() method. 2) Responsiveness Testing One of the easiest ways to test responsive design on different screens is to use the built-in tools of your browser. 3) Stress Testing This is done by simulating an extremely high spike in requests or traffic using a tool built specifically for performance testing sites. 4) Scalability Testing To test the scalability need to consider key aspects such as load, capacity, availability, reliability, and functionality. Load measures the amount of requests or transactions that your web application can handle per unit of time.

First of all we need to define measures and ranges what will be considered as excellent, good, acceptable, and not acceptable. Excellent performance can’t be reached cheaply and related to it we need to understand what performance is good for application we are developing. It depends, as usual.

Analyze performance results by setting goals beforehand. Compare against baselines and benchmarks to spot gaps and trends. Prioritize issues and bottlenecks for focused improvement. Define criteria to interpret results objectively, identifying opportunities for optimization.

GOAL web app dev many times forget the end goal if you want to handle 100,000 users then your architect and resources should be capable of running those. This should be reflected in your testing as well. It is integral to make testing simulate a reasonable amount of traffic according to your goal. I always like to evaluate and analyze my results based on the goal, things to look for in performance testing are resource utilization like CPU, IO, DB query performance and request handle per second this will help you isolate potential bottlenecks

Analyzing performance test results involves evaluating response time, throughput, error rates, resource utilization, latency, concurrency, and scalability. Assess database performance, set benchmarks, and conduct trend analysis. Identify root causes of issues, optimize, and document findings for ongoing improvement.

One way to achieve this is to include performance testing as part of your CI pipeline. Lighthouse CI for instance allows you to set minimum performance scores such that pull requests will have to pass those scores before they can be merged.

1. Follow WPO Framework: - Measure using tools like Lighthouse. - Analyze bottlenecks and areas for improvement. - Optimize with techniques like code modification. - Monitor continuously with tools like Google Analytics. 2. Implement Best Practices: - Optimize code, use caching, and leverage CDNs. - Employ async and deferred loading for scripts. - Optimize images and videos and ensure responsive design. 3. Use Optimization Tools: - Utilize build tools (Webpack, Gulp), CSS preprocessors (Sass), and image optimization tools (ImageOptim, Cloudinary). - Integrate with CDNs like Cloudflare for global content distribution.

Identification of Bottlenecks: Analyzes the results to identify bottlenecks, such as large files, render-blocking scripts, or slow HTTP requests. These items can negatively affect performance. Key Metrics: Pay attention to key metrics like First Contentful Paint (FCP), Largest Contentful Paint (LCP), and Time to Interactive (TTI). These metrics offer valuable insights into the user experience. How to improve and optimize the performance of your web application portfolio Resource Optimization: Minify and combine CSS and JavaScript files, optimize images and use compression techniques to reduce loading time. Efficient Caching: Implement caching strategies to reduce server load and improve loading times for returning users.

It is crucial to evaluate web application performance from the perspective of user experience. After developing your application, it is important to thoroughly test its performance in both controlled laboratory settings and real-world situations. Employing analytics tools can help you assess how the application's performance affects your business metrics. For example, if you are monitoring e-commerce conversions, you can create reports to examine their connection with the application's performance. If there is a significant correlation, prioritizing performance optimization becomes not only advantageous but also necessary for achieving business success.

Optimizing your web application portfolio involves streamlining code, implementing caching and CDNs, compressing assets, optimizing images, and employing asynchronous loading. Focus on database efficiency, scale servers, use load balancing, and ensure responsive design. Monitor performance, prioritize content, consider PWAs, and adopt HTTP/2 with HTTPS. Evaluate third-party services and conduct regular testing for ongoing improvement.

Optimize code, server-side operations, Optimize database queries and server-side code and utilize CDNs. Implement continuous monitoring and address issues proactively.

1. Build a Dedicated Website: - Feature test results, metrics, and visuals. - Ensure a responsive and clean design. 2. Use Social Media: - Share your portfolio on platforms to engage a broader audience. 3. Write a Blog Post: - Narrate your journey with insights and strategies. - Include references and resources. 4. Include Testimonials: - Feature client or user testimonials and case studies. 5. Highlight Achievements: - Showcase awards, certifications, or community contributions. 6. Stay Updated: - Regularly update your portfolio with new projects and achievements.

Showcasing your web application portfolio's performance is an essential aspect of demonstrating your skills and the quality of your work. Here are some important points to consider when showcasing the performance of your web applications in portfolio 1. Page Load Time 2. Responsiveness 3. Scalability 4. CDN Integration 5. Network Performance 6. Caching Strategies 7. Optimized Assets 8. Database Optimization 9. Documentation and Explanations Remember to tailor your presentation of performance achievements to your target audience, whether they are technical recruiters, potential clients, or fellow developers. Provide evidence, context, and a narrative that showcases your skills and commitment to delivering high-performance web applications.

Effectively showcasing your web application portfolio performance involves presenting key metrics, employing visual comparisons, and providing detailed case studies. Utilize interactive demos for a hands-on experience and highlight user-centric improvements, supported by testimonials. Emphasize mobile responsiveness and use visual progress bars to illustrate optimization stages. Clearly communicate the technological stack employed through infographics, offering a comprehensive overview of your expertise in performance optimization. This combination of data visualization and user-focused narratives enhances your portfolio's impact and communicates the tangible benefits of your optimization efforts.

Document the performance matrix. - Do regular profiling the the performance of your web application and publish the result of that in your documentation - Use some performance testing framework to get some data. -

A Performance Metrics web page open to the public provides a means to represent essential metrics like load times. This can show performance overtime with key improvements overlayed. This not only demonstrates the effort to provide a high quality experience but allows the business to attract talent. Testimonials adds a human touch, showcasing real-world scenarios where your application's made a positive impact on users or businesses.

Performance Engineering (PE) as a shift-left strategy plays a pivotal role in enhancing the performance testing experience. By incorporating performance considerations early in the software development lifecycle, it ensures that performance is not just an afterthought but a fundamental aspect of development. Testing each component for performance early on, even with basic metrics like average response time in a development environment, allows for early detection and resolution of performance issues. This proactive approach minimizes costly rework and delays that typically occur when performance testing is left for the later stages of development.

I always use the Lighthouse Chrome dev tool for measuring my web application performance and quality. We can use the failing audits as indicators of how to improve the web page. Lighthouse also provides best practices audit which helps us to follow the coding standards.

Gather user feedback to identify additional performance issues. Test on various devices and browsers for compatibility. Ensure that performance optimizations do not compromise security.

gtmetrix.com is my favourite tool to check website performance in general, because it gives me a comprehensive report that I can share with customers to let them know where is the problem. Chrome DevTools + Lighthouse will give you insight enough to investigate the problem and hopefully solve it.

Often times the environment in which the performance test doesn't always meet real world scenarios. A web application that works within a local network would work differently than one with satellite locations in remote locations who would VPN over a satellite location. Relative distance to services or application artifacts play a key role in performance of an application. Local script performance is important but it is only one piece of the performance puzzle. When considering speed of delivering static site assets a distributed CDN like Cloudflare and Akamai offer options for quick delivery of static assets increasing initial load speed.