allocator ---(2)

Most of the situation the stl default allocator is good enough to handle memory allocation.
But I still did a test on BOOST allocator and STL default allocator.
The result is BOOST pool_allocator is faster and more robust than STL default allocator.

class a
{
public:
a(){}
private:
int t;
//long t1;
};
BOOST_AUTO_TEST_CASE( pool )

{

boost::shared_ptr<Timer> timer(new Timer());
std::vector<a,boost::pool_allocator<a>> v(100000000);
//boost::singleton_pool<boost::pool_allocator_tag, sizeof(int)>::release_memory();

std::cout<<"Time spent on pool_allocator with constructor call: " << timer->elapsed()<<std::endl;


timer->restart();
std::vector<a> v2(100000000);
std::cout<<"Time spent on default allocator with constructor call: " << timer->elapsed()<<std::endl;

}

1> Time spent on pool_allocator with constructor call: 13.1741
1> Time spent on default allocator with constructor call: 16.1502

However if I remove the comment on the class a
STL will throw the exception unknown location(0): fatal error in "pool": std::bad_alloc: bad allocation
while boost::pool_allocator is working fine still.