How I Optimized a Spring Boot Application to Handle 1M Requests/Second

source: linkedin.com

Have you ever wondered how some websites can handle millions of users at once without crashing? Today, I’m going to share how I took a regular Spring Boot application and made it super fast — capable of handling 1 million requests every second. Don’t worry if you’re not a tech genius — I’ll explain everything in simple terms and show you real examples that you can use in your own projects.

The Starting Point: My Basic Spring Boot App

When I first built my application, it was just a basic Spring Boot service that managed user data for an online store. It worked fine with a few hundred users, but as soon as we hit thousands of users, things started to slow down. Pages took forever to load, and sometimes the system would crash completely.

Here’s what my initial setup looked like:

@SpringBootApplication
public class BasicOnlineStoreApplication {
    public static void main(String[] args) {
        SpringApplication.run(BasicOnlineStoreApplication.class, args);
    }
}

@RestController
public class ProductController {
    @Autowired
    private ProductService productService;
    
    @GetMapping("/products")
    public List<Product> getAllProducts() {
        return productService.findAll();
    }…