我比较了快速排序（普通，递归）和线程快速排序（使用线程）。我发现普通快速排序比线程快速排序快。是这样吗？我觉得我做错了什么。
代码如下：

public class QuickSort implements SortAlgorithm {
    public void Sort(Integer[] array) {
        Sort(array, 0, array.length-1);
    }

    private void Sort(Integer[] array, Integer low, Integer high) {
        if (low < high) {
            Integer pivot = partition(array, low, high);
            Sort(array, low, pivot-1);
            Sort(array, pivot+1, high);
        }
    }

    private Integer partition(Integer[] array, Integer low, Integer high) {
        Integer pivot = array[high];  
        Integer i = (low-1);
        for (Integer j=low; j<high; j++) 
            if (array[j] < pivot) { 
                i++; 
                Integer temp = array[i]; 
                array[i] = array[j]; 
                array[j] = temp; 
            } 

        Integer temp = array[i+1]; 
        array[i+1] = array[high]; 
        array[high] = temp; 

        return i+1; 
    }
}

public class ThreadsQuickSort extends Thread implements SortAlgorithm {
    private Integer low, high;
    private Integer[] array;

    public ThreadsQuickSort() {
        ;
    }

    public ThreadsQuickSort(Integer[] array, Integer low, Integer high) {
        this.array = array;
        this.low = low;
        this.high = high;
    }

    public void run() {
        Sort(array, low, high);
    }

    public void Sort(Integer[] array) {
        Sort(array, 0, array.length - 1);
    }

    private void Sort(Integer[] array, Integer low, Integer high) {
        if (low < high) {
            Integer pivot = partition(array, low, high);
            ThreadsQuickSort lowQSort = new ThreadsQuickSort(array, low, pivot - 1);
            lowQSort.start();
            ThreadsQuickSort highQSort = new ThreadsQuickSort(array, pivot + 1, high);
            highQSort.start();
            try {
                lowQSort.join();
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
            try {
                highQSort.join();
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
    }

    private Integer partition(Integer[] array, Integer low, Integer high) {
        Integer pivot = array[high];  
        Integer i = (low-1);
        for (Integer j=low; j<high; j++) 
            if (array[j] < pivot) { 
                i++; 
                Integer temp = array[i]; 
                array[i] = array[j]; 
                array[j] = temp; 
            } 

        Integer temp = array[i+1]; 
        array[i+1] = array[high]; 
        array[high] = temp; 

        return i+1; 
    }
}

main函数使用这两种算法对10000个项目的数组进行排序，并获得它们的执行时间。获得以下输出：

Single array sorted in 11 ms
The array was successfully sorted
Threaded array sorted in 6378 ms
The array was successfully sorted

我的问题是，这是否是良好的编码和输出是预期的。这与线程化快速排序的实现无关。