The most popular implementations of futures, including std::future
, use dynamic allocation and type erasure in order to allow composition of futures into fork/join asynchronous computation graphs. While this overhead is unavoidable when the control flow of the asynchronous graph depends on run-time conditions, it is unnecessary when the "shape" of the computation graph is known at compile-time.
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Is it possible to implement composable futures without dynamic allocation and type erasure?
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Is it worth it?
After a brief overview of the upcoming std::experimental::future
additions focused on composability, this talk answers these questions showing the train of thought behind the design and implementation of an experimental future library, step-by-step. Running time, compilation time, and generated assembly benchmarks/comparisons will be provided and analyzed.
The code covered in the talk will make use of C++17 language and library features, that will be explained throughout the presentation. The intended audience for the talk should be familiar with most C++11/14 language features and with std::future
(or boost::future
). Knowledge of C++17 features is helpful but not required.