Performance and load testing guides — measure, benchmark, and optimize your app before it hits production.
Performance Testing
Synthetic monitoring tells you your site is up. Real User Monitoring (RUM) tells you what experience your actual users are having. These are different questions with different answers. A site can pass every synthetic check and still be slow for users on mobile networks in Southeast Asia, or fast in
Performance Testing
A performance budget is a constraint: "this JavaScript bundle cannot exceed 300KB." The goal isn't to have a target to aim at—it's to make building things that exceed the target impossible. A budget that can be bypassed isn't a budget; it&
Load Testing
BlazeMeter suits enterprises needing JMeter compatibility and multi-protocol support. Loader.io wins for quick HTTP API tests with minimal setup. k6 Cloud offers the best developer experience with code-first tests and generous free tier. Your choice depends on team size, budget, and scripting preference. Cloud load testing has
BlazeMeter
BlazeMeter runs JMeter, Gatling, Locust, and k6 scripts in the cloud across multiple geographic regions. Upload your existing scripts, configure geographic distribution and user counts, run tests, and get unified performance reports without managing load generator infrastructure. The biggest bottleneck in load testing isn't script writing—it'
Performance Testing
A performance budget defines the maximum acceptable values for performance metrics on your application. A bundle size budget says "our main JavaScript bundle must stay under 200KB." A Core Web Vitals budget says "LCP must stay under 2.5s." Without enforcement, these are wishes. With CI
Performance Testing
Running a large load test on your own infrastructure is painful: provisioning machines, managing networking, cleaning up after. BlazeMeter eliminates this by running your JMeter, Gatling, or Locust scripts in cloud infrastructure on demand, scaling to millions of virtual users without touching a server. This guide covers BlazeMeter's
Load Testing
Running load tests manually after every deployment is a discipline that erodes over time. Teams get busy, deployments speed up, and performance regressions ship silently until a spike in traffic exposes them. BlazeMeter's CI/CD integrations solve this by making performance testing an automatic gate in your deployment
Load Testing
Running a load test and looking at one average response time number misses most of what the test is telling you. BlazeMeter's reporting gives you a layered view of performance data — from the high-level summary to per-transaction drill-down. Knowing how to read these reports is
Java
async-profiler is a low-overhead sampling profiler for JVM applications that generates flame graphs showing where CPU time is spent. YourKit is a commercial profiler with deeper analysis. This guide covers attaching both profilers to running JVM processes, reading flame graphs, finding memory leaks, and profiling in production environments.
Load Testing
Every "Artillery vs k6 vs JMeter" comparison online has the same "resource usage: Moderate/Low/High" row and no numbers behind it. We got tired of repeating that without evidence, so we built a fixed target server, ran all three tools against it with matched load
Load Testing
A load test that only hits one endpoint tells you how fast that endpoint is. It doesn't tell you how your system behaves when users log in, search for products, add items to a cart, and check out — all at the same time, with realistic delays between actions.
Load Testing
Out of the box, Artillery gives you latency percentiles and status code counts. That's a starting point, but for serious load testing you need custom assertions, metrics that go to your observability stack, and hooks to run custom logic during tests. Artillery's plugin system covers all