std::jthread::hardware_concurrency

< cpp‎ | thread‎ | jthread

 
C++
 
线程支持库
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std::jthread
 
[[nodiscard]] static unsigned int hardware_concurrency() noexcept;
 (C++20 起)

返回实现支持的并发线程数。应该只把该值当做提示。

参数

（无）

返回值

支持的并发线程数。若该值非良定义或不可计算，则返回 ​0​ 。

示例

运行此代码
#include <iostream>
#include <thread>
 
int main() {
    unsigned int n = std::jthread::hardware_concurrency();
    std::cout << n << " concurrent threads are supported.\n";
}

可能的输出： 

4 concurrent threads are supported.

参阅

(C++17)
 避免假共享的最小偏移
促使真共享的最大偏移
(常量)