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I wasn't able to find this information neither in the Reference Manual, nor by Google - what is the time complexity of the

*push_back()*method of

*parallel_vector*? According to the Wikipedia article for

*std::vector*this operation has an amortized complexity

*O(1)*. How is it for the parallel relative ?

Thank you in advance and best regards

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Quoting - bartlomiej

*what is the time complexity of the*

*push_back()*method of*parallel_vector*? According to the Wikipedia article for*std::vector*this operation has an amortized complexity*O(1)*. How is it for the parallel relative ?tbb::concurrent_vector has the same average complexity of push_back() method.

Most of the time, it just increases the size counter and stores an item. However, when capacity is not enough to store the item, push_back() extends the vector by adding one more segment. It is similar to resizing of std::vector but actually requires even less effort because it doesn't have to move existing items. Anyway, less initial capacity --> more resize operations --> more overhead. See also my blog for more information.

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Quoting - bartlomiej

*what is the time complexity of the*

*push_back()*method of*parallel_vector*? According to the Wikipedia article for*std::vector*this operation has an amortized complexity*O(1)*. How is it for the parallel relative ?tbb::concurrent_vector has the same average complexity of push_back() method.

Most of the time, it just increases the size counter and stores an item. However, when capacity is not enough to store the item, push_back() extends the vector by adding one more segment. It is similar to resizing of std::vector but actually requires even less effort because it doesn't have to move existing items. Anyway, less initial capacity --> more resize operations --> more overhead. See also my blog for more information.

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I'm so ashamed - if I googled concurrent vector, instead of "parallel vector", oops... I'm so sorry.

And thanks once more !

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