Question

如何使用C或C++编程获取电脑CPU使用率？如何使用C或C++获取指定进程的CPU使用率？

Answer 1

得到cpu占有率的API函数：

GetSystemTimes

得到内存使用情况的API函数：

GlobalMemoryStatusEx Function

Retrieves information about the system's current usage of both physical and virtual memory.

GetPerformanceInfo Function

Retrieves the performance values contained in the PERFORMANCE_INFORMATION structure

获取特定程序的内存使用情况用：

GetProcessMemoryInfo Function

Retrieves information about the memory usage of the specified process.

#define _WIN32_WINNT   0x0501

#include <Windows.h>

#include <iostream> 

using   namespace   std;

__int64 CompareFileTime ( FILETIME time1, FILETIME time2 )

{

__int64 a = time1.dwHighDateTime << 32 | time1.dwLowDateTime ;

__int64 b = time2.dwHighDateTime << 32 | time2.dwLowDateTime ;

return   (b - a);

}

void main() 

{ 

HANDLE hEvent;

BOOL res ;

FILETIME preidleTime;

FILETIME prekernelTime;

FILETIME preuserTime;

FILETIME idleTime;

FILETIME kernelTime;

FILETIME userTime;

res = GetSystemTimes( &idleTime, &kernelTime, &userTime );

preidleTime = idleTime;

prekernelTime = kernelTime;

preuserTime = userTime ;

hEvent = CreateEvent (NULL,FALSE,FALSE,NULL); // 初始值为 nonsignaled ，并且每次触发后自动设置为nonsignaled

while (1){

WaitForSingleObject( hEvent,1000 ); //等待500毫秒

res = GetSystemTimes( &idleTime, &kernelTime, &userTime );

int idle = CompareFileTime( preidleTime,idleTime);

int kernel = CompareFileTime( prekernelTime, kernelTime);

int user = CompareFileTime(preuserTime, userTime);

int cpu = (kernel +user - idle) *100/(kernel+user);

int cpuidle = ( idle) *100/(kernel+user);

cout << "CPU利用率:" << cpu << "%" << "      CPU空闲率:" <<cpuidle << "%" <<endl;

preidleTime = idleTime;

prekernelTime = kernelTime;

preuserTime = userTime ;

}

}