Webdriver is causing a memory leak in my spring boot application. Even after the driver quits, the memory is not fully released causing a memory leak.

I’m running 2 separate threads and each thread follow some steps each time they are requested:

1. Starts the driver;
2. Navigates to a webpage, in this example it is google.com;
3. Close the driver;

Here is the code I wrote:

**Main class: **
`@SpringBootApplication
@ServletComponentScan
public class App {

public static void main(String[] args) throws IOException {
    ApplicationContext context = SpringApplication.run(App.class, args);    
    
    //REQUESTING THE ENDPOINT THROUGH CODE
    RestTemplate restTemplate = context.getBean(RestTemplate.class);
    restTemplate.getForEntity("http://localhost:8080/hello", Void.class);
}

}`

**Config class: **
`@Configuration
@EnableAsync
public class AsyncConfig {

@Bean(name="asyncTaskExecutor")
public Executor asyncTaskExecutor(){
    System.out.println("CONFIGURING ASYNC TASKS");
    ThreadPoolTaskExecutor executor = new ThreadPoolTaskExecutor(); 
    executor.setCorePoolSize(2); 
    executor.setMaxPoolSize(2); 
    executor.setQueueCapacity(100); 
    executor.setThreadNamePrefix("Async Thread-"); 
    executor.initialize();
    return executor; 
}


// Configuração do RestTemplate
@Bean
public RestTemplate restTemplate(RestTemplateBuilder builder) {
    return builder.build();
}

}
`

**Service class: **
`
@Service
public class MyService{

private static ThreadLocal<WebDriver> driverThreadLocal = ThreadLocal.withInitial(() -> null);
public static WebDriver getDriver() {
    return driverThreadLocal.get();
}

public static void setDriver(WebDriver driver) {
    driverThreadLocal.set(driver);
}

public static void quitDriver() {
    getDriver().quit();
    driverThreadLocal.remove();
}   

@Async("asyncTaskExecutor")
    public void scrappingtask() throws IOException {
        System.out.println("REQUEST STARTS");
        System.out.println("Thread group: "+Thread.currentThread().getThreadGroup());
        System.out.println("Thread name: " + Thread.currentThread().getName());
        System.out.println("Thread id: " + Thread.currentThread().getId());
    
    
    if (getDriver() == null) {
        System.out.println("*******WEBDRIVER START FOR THE THREAD "+ Thread.currentThread().getName()); 
        System.setProperty("webdriver.chrome.driver","YOUR_CHROME_DRIVER_EXE_PATH"); 
        ChromeOptions options = new ChromeOptions();
        options.addArguments("--headless");
        options.addArguments("--disable-cache");
        driverThreadLocal.set(new ChromeDriver(options));
    } 
    
    System.out.println("WEBDRIVER'S SESSION_ID FOR THE THREAD "+ Thread.currentThread().getName()+":"+((ChromeDriver)driverThreadLocal.get()).getSessionId());

    getDriver().get("https://google.com");
    
    try {
        Thread.sleep(5000);
    } catch (InterruptedException e1) {
        // TODO Auto-generated catch block
        e1.printStackTrace();
    }
    
    System.out.println("REQUEST ENDS");
    quitDriver(); 
}

}
`

**Test cases: **
`
@Controller
public class TestCases {

@Autowired
private MyService myservice;

@GetMapping("/hello")
    public synchronized void runtestcases() throws IOException {
        int i;
        for (i = 1; i <= 10; i++) {
            try {
                Thread.sleep(10000);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
        
        System.out.println(i);
        try {
            myservice.scrappingtask();
        } catch (Exception e) {
        // TODO Auto-generated catch block          
        e.printStackTrace();
        }
    }       
}

}
`

I was expecting to have a heap memory always at the same level of beggining of the process, but it keeps increasing as we can see on the images below:

VisualVM monitor screen

Heap Dump