From: Thorsten Ottosen (tottosen_at_[hidden])
Date: 2006-01-04 11:48:25
Thorsten Ottosen wrote:
> axter wrote:
>
>>This is a continuation on a thread discussion advocating replacing the boost
>>pointer containers with cow_ptr as the default pointer containers.
>
> Test performance for initializing and copying container of pointers.
>
> vector<copy_ptr<Shape> > 0.42 s
>
> boost::ptr_vector<Shape> 0.42 s
>
> vector<cow_ptr<Shape> > 0.09 s
> >>>>>>>>>>>>>>>>>>
>
> cow_ptr seems to win here. I can't figure out why cow_ptr is so much
> faster. ptr_vector uses cloning, of course, whereas cow_ptr does
> something else.
>
I further tried to add the proper return type to the functions, such
that ptr_vector<T> returns by auto_ptr< ptr_vector<T> > and vector<T> as
vector<T>. On top of this, I save the return-value and called size() on it.
This gave:
Test performance for initializing and copying container of pointers.
vector<copy_ptr<Shape> > 1.42 s
boost::ptr_vector<Shape> 0.81 s
vector<cow_ptr<Shape> > 0.13 s
But this test is a bit unfair: we create copies of the vector, but we
never mutate that copy. A fair test would mutate all the elements.
-Thorsten