Re: [boost] [Block Pointer][Container] Works - Take 2

On 03/05/2016 05:30 AM, Peter Dimov wrote:

Phil Bouchard wrote:

...

- I removed the usage of an allocator. Now there is no need for any allocator anymore.

I'm not sure I see how this would work. If you have

void f() { vector v; }

You are close to a valid point. Although this case works: https://github.com/philippeb8/block_ptr/blob/master/example/block_ptr_test2.... If you have a cycle on the heap that is not owned by a root pointer from the stack then I think the memory blocks will still be deleted. If you look at how it is implemented, when the number of pointers from the stack reaches 0 or if it is already 0 then all memory blocks will be wiped out: https://github.com/philippeb8/block_ptr/blob/master/include/boost/block_ptr.... I thought there would be a leak there but thinking about it twice I believe it should be fine. I'll try some other strange use case...

block_ptr> v2;

for the second case allows you to distinguish between the two.

Ideally I could do that but the implementation of the allocator for containers turns out to be a real challenge. The code is much cleaner "but" since it allocates more proxies, despite using the fast pool allocator, that still slows down the overall performance: make: auto_ptr: 26164754 ns shared_ptr: 27554248 ns block_ptr: 144391600 ns new: auto_ptr: 22210062 ns shared_ptr: 46869206 ns block_ptr: 138204822 ns block_ptr<> is now 300% slower than shared_ptr<> for this type of benchmark. Regards, -Phil