async

The framework for supporting a style of parallel programming in which problems are solved by (recursively) splitting them into subtasks that are solved in parallel, waiting for them to complete, and then composing results.

The fork/join framework provides a very straightforward and intuitive structure to conquer problems.

example

int sequentialFibonacci(n);

void combineFibonacci(int x, int y, function<void(int)> sendResult)
{
  sendResult(x + y);
}

void calculateFibonacci(asio::io_service& theService, int n, function<void(int)> onComplete)
{
  if (n <= threshold)
  {
    onComplete(sequentialFibonacci(n));
  }
  else
  {
    async<void(int), void(int)>(
        io_service,
        bind(calculateFibonacci, ref(theService), n - 1, _1),
        bind(calculateFibonacci, ref(theService), n - 2, _1),
        bind(combineFibonacci, _1, _2, onComplete));
  }
}