randyhbh

Anatomy of Spring Boot Start Up Timing

When a Spring Boot app starts up with default (INFO) logging, there are some noticeable gaps (pauses). It's worth focusing on the gaps when looking for efficiency savings because of the amount of time they take, and because no-one bothered to log anything, so the chances are the app is doing something repetitive. We can tweak the logging levels to try and fill in the gaps and find out what is going on in there.

Basic empty web app with actuators has three such gaps:

0                                                                        1410ms
|------|---------------------------|-----|------|---------|--------|--------|
       |           578             |     |144(5)|         | 133(6) |

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private static final Scanner scanner = new Scanner(System.in);

    public static void main(String[] args) {
        String[] nm = scanner.nextLine().split(" ");

        int n = Integer.parseInt(nm[0]);

        int m = Integer.parseInt(nm[1]);

        int[][] queries = new int[m][3];

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public class Main {

    public static void main(String[] args) {
        int [] a = new int[]{4,3,1,2};
        minimumSwaps(a);
    }
    static int minimumSwaps(int[] arr) {
        int swapsCount = 0;
        int arraySize = arr.length;

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    static void minimumBribes(int[] q) {
        int ans=0;

        for(int i=q.length -1; i >= 0 ; i--) {
            if (q[i] - (i+1) > 2) {
                System.out.println("Too chaotic");
                return;
            }
            for (int j = Integer.max(0, q[i] - 2); j < i; j++)
                if (q[j] > q[i]) ans++;

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    static int[] rotLeft(int[] a, int d) {
        int [] rotated = new int[a.length];

        for (int i = 0; i <= a.length - 1; i++) {
            rotated[i] = a[(i + d) % a.length];
        }
        return rotated;
    }

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    static int amountOfLetter(String chain, char letter) {
        return chain.chars().mapToObj(i -> (char) i).filter(character -> character.equals(letter))
                .collect(Collectors.toList()).size();
    }

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// Swift 3

extension UIButton {
    
    func pulsate() {
        
        let pulse = CASpringAnimation(keyPath: "transform.scale")
        pulse.duration = 0.6
        pulse.fromValue = 0.95
        pulse.toValue = 1.0