在Windows上创建缓慢的线程

#include <iostream>
#include <thread>

void t1(int& k) {
    k += 1;
};

void t2(int& k) {
    k += 1;
};

int main(int argc,const char *argv[])
{
    int a{ 0 };
    int b{ 0 };

    auto start_time = std::chrono::high_resolution_clock::now();
    for (int i = 0; i < 10000; ++i) {
        std::thread thread1{ t1,std::ref(a) };
        std::thread thread2{ t2,std::ref(b) };
        thread1.join();
        thread2.join();
    }
    auto end_time = std::chrono::high_resolution_clock::now();
    auto time_stack = std::chrono::duration_cast<std::chrono::microseconds>(
        end_time - start_time).count();
    std::cout << "Time: " << time_stack / 10000.0 << " micro seconds" <<
        std::endl;

    std::cout << a << " " << b << std::endl;

    return 0;
}

我发现在Mac OS X上启动一个线程需要34微秒,在Windows上需要340微秒才能完成相同的操作.我在Windows方面做错了吗？这是一个编译问题吗？