2
我有3個單元在https://github.com/spakai/threadpool_future定時測試：單線程VS回調TP VS未來TP
class ThreadPoolTest : public Test {
public:
ThreadPool pool;
std::condition_variable wasExecuted;
std::mutex m;
std::vector<std::shared_ptr<std::thread>> threads;
unsigned int count{0};
void incrementCountAndNotify() {
std::unique_lock<std::mutex> lock(m);
++count;
std::cout << count << std::endl;
wasExecuted.notify_all();
}
void waitForNotificationOrFailOnTimeout(unsigned expectedCount, int milliseconds=80000) {
std::unique_lock<std::mutex> lock(m);
ASSERT_THAT(wasExecuted.wait_for(lock, std::chrono::milliseconds(milliseconds), [&] { return count == expectedCount; }), Eq(true));
}
bool hasDuplicates(const std::vector<int> & birthdays) {
std::set<int> uniqueBirthdays(birthdays.begin(), birthdays.end());
return (uniqueBirthdays.size() != birthdays.size());
}
std::vector<int> generateNumbers(const int popSize) {
std::vector<int> list;
std::random_device rd;
std::default_random_engine dre(rd());
std::uniform_int_distribution<int> di(0,365);
for(int i{0}; i < popSize ; i++) {
list.push_back(di(dre));
}
return list;
}
void TearDown() override {
for (auto& t: threads) t->join();
}
};
TEST_F(ThreadPoolTest,TimingTestWithFuture) {
pool.start(4);
std::vector<std::future<unsigned long long>> results;
auto work = [](int n) {
unsigned long long factorial = 1;
for(int i = 1; i <=n; ++i) {
factorial *= i;
}
return factorial;
};
TestTimer timer("4-sized-TP with Future",0);
for (int i = 5; i < 60 ; i++) {
results.push_back(pool.submit(work,i));
}
for(unsigned int i = 0; i< results.size(); i++) {
results.at(i).get();
}
}
TEST_F(ThreadPoolTest,TimingTestWithCallback) {
pool.start(4);
std::vector<unsigned long long> results;
TestTimer timer("4-sized-TP-Callback",0);
for (int n = 5; n < 60 ; n++) {
auto work = [&]() {
unsigned long long factorial = 1;
for(int i = 1; i <=n; ++i) {
factorial *= i;
}
{
std::lock_guard<std::mutex> guard(m);
results.push_back(factorial);
}
incrementCountAndNotify();
};
pool.add(work);
}
waitForNotificationOrFailOnTimeout(55);
}
TEST_F(ThreadPoolTest,TimingTestWithoutTP) {
std::vector<unsigned long long> results;
auto work = [](int n) {
unsigned long long factorial = 1;
for(int i = 1; i <=n; ++i) {
factorial *= i;
}
return factorial;
};
TestTimer timer("In Sequence",0);
for (int i = 5; i < 60 ; i++) {
results.push_back(work(i));
}
for(unsigned int i = 0; i< results.size(); i++) {
results.at(i);
}
}
我一個4 CPU的計算機上運行的情況下測試該代碼線程池。我得到的計時結果顯示單線程速度最快，而未來速度最慢。
4尺寸-TP與未來時間採取= 2.364ms
4尺寸-TP-回叫時間採取= 1.103ms
在序列時間採取= 0.026ms
我期待時間安排將按相反的順序進行。 我做測試的方式錯了嗎？或者它是我的代碼？
新的測試這將是CPU重
TEST_F(ThreadPoolTest,BirthdayParadoxInSequenceTimingTest) {
std::vector<int> results;
TestTimer timer("Birthday Paradox :: In Sequence",0);
std::vector<int> popList = {10,23,30,40,50,60,70,80,90,100,120,150};
for(auto it=popList.begin(); it!=popList.end(); ++it) {
int id = *it;
int dup{0};
for(int i{0}; i< 100000; i++) {
auto list = generateNumbers(id);
if(hasDuplicates(list)) ++dup;
}
results.push_back(dup);
}
for(unsigned int i = 0; i< results.size(); i++) {
results.at(i);
}
}
TEST_F(ThreadPoolTest,BirthdayParadoxTPWithFutureTimingTest) {
std::vector<int> popList = {10,23,30,40,50,60,70,80,90,100,120,150};
pool.start(4);
std::vector<std::future<int>> results;
TestTimer timer("4-sized-TP with Future",0);
for(auto it=popList.begin(); it!=popList.end(); ++it) {
int id = *it;
auto work = [&](int pop) {
int dup{0};
for(int i{0}; i < 100000 ; i++) {
auto list = generateNumbers(pop);
if(hasDuplicates(list)) ++dup;
}
return dup;
};
results.push_back(pool.submit(work,id));
}
for(unsigned int i = 0; i< results.size(); i++) {
results.at(i).get();
}
}
TEST_F(ThreadPoolTest,BirthdayParadoxTPWithCallBackTimingTest) {
std::vector<int> popList = {10,23,30,40,50,60,70,80,90,100,120,150};
pool.start(4);
std::vector<int> results;
TestTimer timer("4-sized-TP with Callback",0);
for(auto it=popList.begin(); it!=popList.end(); ++it) {
int id = *it;
auto work = [&,id]() {
int dup{0};
for(int i{0}; i < 100000 ; i++) {
auto list = generateNumbers(id);
if(hasDuplicates(list)) ++dup;
{
std::lock_guard<std::mutex> guard(m);
results.push_back(dup);
}
}
incrementCountAndNotify();
};
pool.add(work);
}
waitForNotificationOrFailOnTimeout(12);
}
結果雖然還沒有我期待
在序列時間採取= 37555.7ms
4級-TP與未來所用時間= 62544.8ms
帶回調時間的4碼TP = 62563.6ms
完整的代碼和測試是在https://github.com/spakai/threadpool_future
計算階乘對於CPU來說不是一項具有挑戰性的任務。所有的開銷都發生在上下文切換和鎖定中。嘗試在它上面投擲稅收問題。 – paddy
好吧，我改變了一些CPU的重量。時間還沒有結束。當我使用top時，序列測試顯示CPU接近100％，未來和回調顯示接近400％。我已經更新了上面的新測試。 – spakai
我試圖複製你的行爲。在回購的文件中有一些錯誤。第一個TThreadPoolTest.cpp缺少一個'#include'，其次是cmakelists.txt中的'sources'變量需要包含TestTimer.cpp。 可悲的消息是，我得到了類似的時間行爲。 –
OutOfBound