Paolo Carlini - Re: Call for compiler help/advice: atomic builtins for v3 (original) (raw)

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Paolo Carlini wrote:

                                                   And, that if

__exchange_and_add is showing up on the top of the profile, the fix probably isn't inlining -- it's to work out a way to make less use of atomic operations.

I want to add that we are certainly going in this direction, with a non-refcounted string for the next library ABI, also available as an extension, a preview for 4.1.

On the other hand, you cannot avoid atomic operations completely in the library, and in some areas, for instance tr1::shared_ptr, it's really the best you can use, using lock-free programming, to achieve MT-safety and good performance.

Also, I think an user yesterday had a good point: we should also make possible a configuration option enabling to build the library optimized for single thread. To be fair, Gerald Pfeifer also suggested that a lot of time ago...

Paolo.

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