loki的小型对象疑惑

[guolihui112]

想用loki的小型对象内存池。但是测试一个小例子发现，比正常的还要慢， 不知道怎么回事：
在xcode测试结果如下：

small object (16byte)
default
stop watch ...stop watch : 0.78112
Loki::SmallObject
stop watch ...stop watch : 4.89299
big object (8000byte)
default
stop watch ...stop watch : 0.789333
Loki::SmallObject
stop watch ...stop watch : 1.52838

例子是这样的：

#include <loki/SmallObj.h>
#include <iostream>

template <class Type = int>
class StopWatch
{
public:
    StopWatch()
    {
        std::cout << "stop watch ...";
        m_beginClock = clock();
    }
    
    ~StopWatch()
    {
        clock_t endClock = clock();
        clock_t interval = endClock-m_beginClock;
        double seconds = (double)interval / CLOCKS_PER_SEC;
        std::cout << "stop watch : " << seconds << std::endl;
    }
    
private:
    clock_t m_beginClock;
};

enum enSmallObjectSize
{
    Size_Small = 4,
    Size_Big = 2000,
};


class A { int a[Size_Small]; };
class B : public Loki::SmallObject<> { int b[Size_Small]; };

class D { int d[Size_Big]; };
class E : public Loki::SmallObject<> { int e[Size_Big]; };

int test() {
	std::cout << "small object (" << sizeof(int) * Size_Small << "byte)" << std::endl;
	{
		std::cout << "default" << std::endl;
		StopWatch<>* sw = new StopWatch<>;
		for (int j = 0; j < 10; j++) {
            for (int i = 0; i < 1000000; i++) {
                A* a = new A;
                delete a;
            }}
		delete sw;
	}
	{
		std::cout << "Loki::SmallObject" << std::endl;
		StopWatch<>* sw = new StopWatch<>;
		for (int j = 0; j < 10; j++) {
            for (int i = 0; i < 1000000; i++) {
                B* b = new B;
                delete b;
            }}
		delete sw;
	}
	std::cout << "big object (" << sizeof(int) * Size_Big << "byte)" << std::endl;
	{
		std::cout << "default" << std::endl;
		StopWatch<>* sw = new StopWatch<>;
		for (int j = 0; j < 10; j++) {
            for (int i = 0; i < 1000000; i++) {
                D* d = new D;
                delete d;
            }}
		delete sw;
	}
	{
		std::cout << "Loki::SmallObject" << std::endl;
		StopWatch<>* sw = new StopWatch<>;
		for (int j = 0; j < 10; j++) {
            for (int i = 0; i < 1000000; i++) {
                E* e = new E;
                delete e;
            }}
		delete sw;
	}
    
	return 0;
}

[guolihui112]

[Quote=引用 3 楼 的回复:]

1.默认实现可以有针对平台的优化；
2.长时间随机分配释放小对象，SmallObject的优势较容易体现。
[/Quote]
在windows下测试loki的例子，也是比默认的慢一倍还多。 只能期待2能发挥作用了

[guolihui112]

楼上。。。。 晕

[FrankHB1989]

1.默认实现可以有针对平台的优化；
2.长时间随机分配释放小对象，SmallObject的优势较容易体现。