Scroll to navigation

std::jthread::hardware_concurrency(3) C++ Standard Libary std::jthread::hardware_concurrency(3)

NAME

std::jthread::hardware_concurrency - std::jthread::hardware_concurrency

Synopsis


[[nodiscard]] static unsigned int hardware_concurrency() noexcept; (since C++20)


Returns the number of concurrent threads supported by the implementation. The value
should be considered only a hint.

Parameters


(none)

Return value


Number of concurrent threads supported. If the value is not well defined or not
computable, returns 0.

Example

// Run this code


#include <iostream>
#include <thread>


int main()
{
unsigned int n = std::jthread::hardware_concurrency();
std::cout << n << " concurrent threads are supported.\n";
}

Possible output:


4 concurrent threads are supported.

See also


hardware_destructive_interference_size min offset to avoid false sharing
hardware_constructive_interference_size max offset to promote true sharing
(C++17) (constant)

2024.06.10 http://cppreference.com