[boost] [circular buffer review]

From: Thorsten Ottosen (nesotto_at_[hidden])
Date: 2004-03-12 05:06:16

Hi All,

here is my review of the circular buffer class.

What is your evaluation of the design?
---------------------------------------

The design is good. People can easily learn to use it.
There are some miner things that I would like see changed, like double
versions of push_back and push_front. I don't
understand why both set_capacit and resize are provided and I would like to
see them merged if possible.

I also think push_back should throw an exception if no element is inserted.
This behavior is somewhat different push_back() from a
normal std container. If there are similar cases then I think they should be
looked at again too.

What is your evaluation of the implementation?
-----------------------------------------------
I haven't looked closely at the source code.

What is your evaluation of the documentation?
----------------------------------------------
very good once the exception-safety issues are solved

What is your evaluation of the potential usefulness of the library?
----------------------------------------------------------------
I'm in doubt. The library has efficiency as its hallmark. The  rationale
says that it
gives efficient FIFO queue. So I tried to compare it with std::deque, and
here is my results
of an /O2 build with vc71:

$ ./cbuffer_vs_deque.exe

 circular_buffer<int>: 2.15 s

 deque<int>: 2.84 s

 circular_buffer<string>: 20.59 s

 deque<string>: 18.64 s

The test program is attached; I might have made an error, but if I have not,
then
I don't see the claim as true. In that case I need to see some more evidence
about why
the speed advantages should be so good. It also make me wonder if there is
any need for
circular_buffer_space_optimized.

Did you try to use the library?  With what compiler?  Did you have any
problems?
----------------------------------------------------------------------------
------
yes, with vc7.1; Comeau 4.3.0 could not compile it. It worked fine on vc7.1

How much effort did you put into your evaluation? A glance? A quick reading?
In-depth study?
----------------------------------------------------------------------------
-------------------
A couple of hours with both documentation and code use.

Are you knowledgeable about the problem domain?
-----------------------------------------------------
I don't have experience with embedded applications; I have written stuff in
which performace
was critical and in which specially designed datastructures was necessary.

Do you think the library should be accepted as a Boost library?
---------------------------------------------------------------

Yes if the author can convince me that we really get more performance.
No otherwise.

best regards

Thorsten

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