c++ 11线程测试

#include <ctime>
#include <iostream>
#include <vector>
#include <thread>
#include <atomic>
#include <mutex>

#include <Windows.h>

#define SIZE 1000000

std::atomic<int> g_seq1;
int g_seq2;
int g_seq3;
int g_seq4;

std::atomic_flag af = ATOMIC_FLAG_INIT;
std::mutex mtx;

CRITICAL_SECTION g_criSec;

void ThreadFunc1(int id)
{//原子操作 220ms
    for (int i = 0; i < SIZE; i++)
    {
        ++g_seq1;
    }
}

void ThreadFunc2(int id)
{//atomic_flag 
    for (int i = 0; i < SIZE; i++)
    {
        while (af.test_and_set()) {}
        ++g_seq2;
        af.clear();
    }
}

void ThreadFunc3(int id)
{//mutex 260
    for (int i = 0; i < SIZE; i++)
    {
        mtx.lock();
        ++g_seq3;
        mtx.unlock();
    }
}

void ThreadFunc4(int id)
{//CriticalSection 
    for (int i = 0; i < SIZE; i++)
    {
        EnterCriticalSection(&g_criSec);
        ++g_seq3;
        LeaveCriticalSection(&g_criSec);
    }
}

void ThreadTest1();

void ThreadTest2();

void ThreadTest3();

void ThreadTest4();


int main()
{
    InitializeCriticalSection(&g_criSec);

    ThreadTest1();

    ThreadTest2();

    ThreadTest3();

    ThreadTest4();

    std::cout << std::endl;
    system("pause");
}

/* Output:

ThreadTest1
duration=213
g_seq1=10000000

ThreadTest2
duration=5164
g_seq2=10000000

ThreadTest3
duration=254
g_seq3=10000000

ThreadTest4
duration=2379
g_seq4=0

*/

void ThreadTest1()
{
    time_t tm_start = clock();
    time_t tm_now = 0;
    std::vector<std::thread> vec;
    for (int i = 0; i < 10; i++)
    {
        vec.push_back(std::thread(ThreadFunc1, i));
    }
    for (auto& t : vec)
    {
        t.join();
    }
    tm_now = clock();
    std::cout << std::endl;
    std::cout << __FUNCTION__ << std::endl;
    std::cout << "duration=" << tm_now - tm_start << std::endl;
    std::cout << "g_seq1=" << g_seq1 << std::endl;
}

void ThreadTest2()
{
    time_t tm_start = clock();
    time_t tm_now = 0;
    std::vector<std::thread> vec;
    for (int i = 0; i < 10; i++)
    {
        vec.push_back(std::thread(ThreadFunc2, i));
    }
    for (auto& t : vec)
    {
        t.join();
    }
    tm_now = clock();
    std::cout << std::endl;
    std::cout << __FUNCTION__ << std::endl;
    std::cout << "duration=" << tm_now - tm_start << std::endl;
    std::cout << "g_seq2=" << g_seq2 << std::endl;
}

void ThreadTest3()
{
    time_t tm_start = clock();
    time_t tm_now = 0;
    std::vector<std::thread> vec;
    for (int i = 0; i < 10; i++)
    {
        vec.push_back(std::thread(ThreadFunc3, i));
    }
    for (auto& t : vec)
    {
        t.join();
    }
    tm_now = clock();
    std::cout << std::endl;
    std::cout << __FUNCTION__ << std::endl;
    std::cout << "duration=" << tm_now - tm_start << std::endl;
    std::cout << "g_seq3=" << g_seq3 << std::endl;
}

void ThreadTest4()
{
    time_t tm_start = clock();
    time_t tm_now = 0;
    std::vector<std::thread> vec;
    for (int i = 0; i < 10; i++)
    {
        vec.push_back(std::thread(ThreadFunc4, i));
    }
    for (auto& t : vec)
    {
        t.join();
    }
    tm_now = clock();
    std::cout << std::endl;
    std::cout << __FUNCTION__ << std::endl;
    std::cout << "duration=" << tm_now - tm_start << std::endl;
    std::cout << "g_seq4=" << g_seq4 << std::endl;
}