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From: frank_at_[hidden]
Date: 2005-04-29 19:29:08


On Friday 29 April 2005 23:27, Olaf Krzikalla wrote:

> > But why not
> > using a reference type and storing this in the usual non-instrusive
> > containers?
>
> Performance reasons. Look at Overview, section 'Properties of intrusive
> containers' and then go to Usage, section 'When to use?'. It not only
> mentions your idea, but should answers your question too. In fact, the
> development of these containers was the result of falling in a deep
> performance hole while developing some mathematical algorithms (e.g. a
> fast triangulation algorithm, which needs 3 sequences over the
> vertices). Another example is the open source polygon clipping algorithm
> GPC. A C++ version of GPC could draw huge advantages from Boost.Intrusive.
>

Yep, now I understood. The whole thing is about laying out objects in
memory in an efficient way. Sorry for always talking in critic, but I would
love to suggest to think about memory allocators.
Pool allocators can be utilised greatly to achieve memory layout for
ideal cache heating. I missed that point in the efficiency discussion
of intrusive containers versus non-intrusive containers.
There's no need for any runtime allocation logic at all for
non-intrusive containers, but intrusive containers may compete
with non-intrusive one when applying pool allocators.

Oh, and thank you answering my questions.
These non-instrusive containers provide me some good ideas for
my own work.

Best regards,
Frank.


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