Re: [webkit-dev] std::shared_ptr?

2013-10-26 Thread Benjamin Poulain 
On 10/26/13, 8:51 PM, Brendan Long wrote:
> One of the answers on this Stack Overflow question
> 
> suggests that we can fix the memory issue by using `making_shared`:
> 
>> *use* |make_shared|
>  *to
> allocate them*, because (unfortunately) the normal constructor allocates
> two different blocks: one for the object and one for the counter and
> deleter.
> 
> Unfortunately, it looks like
> 
> they're really slow because they're thread-safe, but that may also apply
> to RefPtr.

RefPtr is not thread-safe.

The count itself is maintained by the objects, not the smart pointer.
The vast majority of objects are not thread-safe either due to obvious
performance problems.

Benjamin
___
webkit-dev mailing list
webkit-dev@lists.webkit.org
https://lists.webkit.org/mailman/listinfo/webkit-dev

Re: [webkit-dev] std::shared_ptr?

2013-10-26 Thread Brendan Long 
One of the answers on this Stack Overflow question

suggests that we can fix the memory issue by using `making_shared`:

> *use* |make_shared|
 *to
allocate them*, because (unfortunately) the normal constructor allocates
two different blocks: one for the object and one for the counter and
deleter.

Unfortunately, it looks like

they're really slow because they're thread-safe, but that may also apply
to RefPtr.
___
webkit-dev mailing list
webkit-dev@lists.webkit.org
https://lists.webkit.org/mailman/listinfo/webkit-dev

Re: [webkit-dev] std::shared_ptr?

2013-10-26 Thread Ryosuke Niwa 
I don't think we can afford to use shared_ptr.  As far as I know, it
allocates a new memory space for each object to be shared.  Doing that for
every DOM node will probably be prohibitively expensive.


- R. Niwa


On Sat, Oct 26, 2013 at 11:16 AM, Brendan Long  wrote:

> On 10/25/2013 06:38 PM, Darin Adler wrote:
> > We are replacing PassOwnPtr and OwnPtr with std::unique_ptr. This is
> > part of a general trend where we are adopting some C++11 language and
> > library features.
> Is there any plan to replace RefPtr with std::shared_ptr too, or is
> there some reason why that would be a bad idea?
> ___
> webkit-dev mailing list
> webkit-dev@lists.webkit.org
> https://lists.webkit.org/mailman/listinfo/webkit-dev
>
___
webkit-dev mailing list
webkit-dev@lists.webkit.org
https://lists.webkit.org/mailman/listinfo/webkit-dev

[webkit-dev] std::shared_ptr?

2013-10-26 Thread Brendan Long 
On 10/25/2013 06:38 PM, Darin Adler wrote:
> We are replacing PassOwnPtr and OwnPtr with std::unique_ptr. This is
> part of a general trend where we are adopting some C++11 language and
> library features.
Is there any plan to replace RefPtr with std::shared_ptr too, or is
there some reason why that would be a bad idea?
___
webkit-dev mailing list
webkit-dev@lists.webkit.org
https://lists.webkit.org/mailman/listinfo/webkit-dev