C-计算cpu的使用情况？

Question

在PHP中可以通过memory_get_usage来查看当前程序的内存使用情况。
不知使用什么办法可以查看当前程序的CPU使用情况？
C语言实现也可以。

Answer 1

1.使用 sys_getloadavg 函数。Note: 本函数未在 Windows 平台下实现。

Answer 2

我觉得你可以使用PHP的exec、system、passthru等函数，直接执行Linux的系统Shell命令或者程序(例如：top命令)，然后返回结果进行分析就行了，这样还更方便。

Answer 3

#pragma once

#define SystemBasicInformation 0
#define SystemPerformanceInformation 2
#define SystemTimeInformation 3

#define Li2Double(x) ((double)((x).HighPart) * 4.294967296E9 + (double)((x).LowPart))

class CCpuUsage
{
public:
CCpuUsage();
~CCpuUsage();

public:
int GetCpuUsage(); //得到系统cpu利用率
int SetRefreshInterval(int milli_sec); //定时刷新间隔

private:
//类型定义
typedef LONG (WINAPI *PROCNTQSI)(UINT,PVOID,ULONG,PULONG);

typedef struct
{
DWORD dwUnknown1;
ULONG uKeMaximumIncrement;
ULONG uPageSize;
ULONG uMmNumberOfPhysicalPages;
ULONG uMmLowestPhysicalPage;
ULONG uMmHighestPhysicalPage;
ULONG uAllocationGranularity;
PVOID pLowestUserAddress;
PVOID pMmHighestUserAddress;
ULONG uKeActiveProcessors;
BYTE bKeNumberProcessors;
BYTE bUnknown2;
WORD wUnknown3;
} SYSTEM_BASIC_INFORMATION;

typedef struct
{
LARGE_INTEGER liIdleTime;
DWORD dwSpare[76];
} SYSTEM_PERFORMANCE_INFORMATION;

typedef struct
{
LARGE_INTEGER liKeBootTime;
LARGE_INTEGER liKeSystemTime;
LARGE_INTEGER liExpTimeZoneBias;
ULONG uCurrentTimeZoneId;
DWORD dwReserved;
} SYSTEM_TIME_INFORMATION;

//变量定义
SYSTEM_PERFORMANCE_INFORMATION SysPerfInfo;
SYSTEM_TIME_INFORMATION SysTimeInfo;
SYSTEM_BASIC_INFORMATION SysBaseInfo;

【kouzhongling】:
double dbIdleTime;
double dbSystemTime;

LONG status;

LARGE_INTEGER liOldIdleTime;
LARGE_INTEGER liOldSystemTime;

PROCNTQSI NtQuerySystemInformation;

int m_nCpuUsage;

//定时
HWND m_hWnd;
int m_nRefreshInterval;//默认为1000毫秒
int m_nTimerID;

private:
static void CalcCpuUsage(HWND hwnd, UINT uMsg, UINT_PTR idEvent, DWORD dwTime);
int OnTimer();
};

inline CCpuUsage::CCpuUsage()
{
//
m_hWnd = NULL;
m_nRefreshInterval = 1000;
m_nTimerID = 1000;
m_nCpuUsage = 0;

//
memset(&liOldIdleTime , 0, sizeof(LARGE_INTEGER));
memset(&liOldSystemTime, 0, sizeof(LARGE_INTEGER));

//
NtQuerySystemInformation = (PROCNTQSI)GetProcAddress(
GetModuleHandle("ntdll") , "NtQuerySystemInformation");
if (!NtQuerySystemInformation)
return;

// get number of processors in the system
status = NtQuerySystemInformation(SystemBasicInformation,&SysBaseInfo,sizeof(SysBaseInfo),NULL);
if (status != NO_ERROR)
return;

// create control for timer
m_hWnd = ::CreateWindow("static", "", 0, 0, 0, 0, 0, NULL, NULL, 0, NULL);
::SetWindowLong(m_hWnd , GWL_USERDATA , (long)(this) );

TIMERPROC tp = (TIMERPROC)CalcCpuUsage;
SetTimer(m_hWnd , m_nTimerID, m_nRefreshInterval, tp);

}

inline CCpuUsage::~CCpuUsage()
{
KillTimer(m_hWnd , m_nTimerID);
DestroyWindow(m_hWnd);
}

inline void CCpuUsage::CalcCpuUsage(
HWND hwnd,
UINT uMsg,
UINT_PTR idEvent,
DWORD dwTime
)

【kouzhongling】:
{
CCpuUsage* pCpu = (CCpuUsage*)::GetWindowLong(hwnd , GWL_USERDATA);

if ( pCpu )
{
pCpu->OnTimer();
}

}

inline int CCpuUsage::OnTimer()
{
status = NtQuerySystemInformation(SystemTimeInformation,&SysTimeInfo,sizeof(SysTimeInfo),0);

if (status!=NO_ERROR)
return 0;

// get new CPU's idle time
status = NtQuerySystemInformation(SystemPerformanceInformation,&SysPerfInfo,sizeof(SysPerfInfo),NULL);
if (status != NO_ERROR)
return 0;

// if it's a first call - skip it
if (liOldIdleTime.QuadPart != 0)
{
// CurrentValue = NewValue - OldValue
dbIdleTime = Li2Double(SysPerfInfo.liIdleTime) - Li2Double(liOldIdleTime);
dbSystemTime = Li2Double(SysTimeInfo.liKeSystemTime) - Li2Double(liOldSystemTime);

// CurrentCpuIdle = IdleTime / SystemTime
dbIdleTime = dbIdleTime / dbSystemTime;

// CurrentCpuUsage% = 100 - (CurrentCpuIdle * 100) / NumberOfProcessors
dbIdleTime = 100.0 - dbIdleTime * 100.0 / (double)SysBaseInfo.bKeNumberProcessors + 0.5;

m_nCpuUsage = (UINT)dbIdleTime;
}

// store new CPU's idle and system time
liOldIdleTime = SysPerfInfo.liIdleTime;
liOldSystemTime = SysTimeInfo.liKeSystemTime;

// wait one second

return 0;
}

inline int CCpuUsage::GetCpuUsage()
{
return m_nCpuUsage;
}

inline int CCpuUsage::SetRefreshInterval(int milli_sec)
{
m_nRefreshInterval = milli_sec;

if ( m_hWnd )
{
TIMERPROC tp = (TIMERPROC)CalcCpuUsage;
SetTimer(m_hWnd, m_nTimerID, m_nRefreshInterval ,tp);
}

return 0;

}

详细看http://www.programfan.com/club/showpost.asp?id=6476

Answer 4

－－－－－－－－－－－－－－
UINT CProcessManager::GetCPUUsageRate()
{
SYSTEM_PERFORMANCE_INFORMATION SysPerfInfo;
SYSTEM_TIME_INFORMATION SysTimeInfo;
SYSTEM_BASIC_INFORMATION SysBaseInfo;
double dbIdleTime; //空闲时间
double dbSystemTime;//系统时间
LONG status;
LARGE_INTEGER liOldIdleTime = {0,0};
LARGE_INTEGER liOldSystemTime = {0,0};

NtQuerySystemInformation = (PROCNTQSI)
GetProcAddress(
GetModuleHandle( "ntdll.dll "),
"NtQuerySystemInformation "
);
if (!NtQuerySystemInformation)
{
return 0;
}

status = NtQuerySystemInformation( // 获取系统处理器位数
SystemBasicInformation,
&SysBaseInfo,
sizeof(SysBaseInfo),
NULL
);
if (status != NO_ERROR)
{
return 0;
}

status = NtQuerySystemInformation( // 获取新的系统时间
SystemTimeInformation,
&SysTimeInfo,
sizeof(SysTimeInfo),
NULL
);
if (status != NO_ERROR)
{
return 0;
}

status =NtQuerySystemInformation( // 获取新的系统空闲时间
SystemPerformanceInformation,

&SysPerfInfo,
sizeof(SysPerfInfo),
NULL
);
if (status != NO_ERROR)
return 0;

if (liOldIdleTime.QuadPart != 0) // 第一次调用将被跳过
{
dbIdleTime = Li2Double(SysPerfInfo.liIdleTime)

- Li2Double(liOldIdleTime);

dbSystemTime = Li2Double(SysTimeInfo.liKeSystemTime)
- Li2Double(liOldSystemTime);

dbIdleTime = dbIdleTime / dbSystemTime; // 当前CPU空闲＝空闲时间/系统时间

dbIdleTime = 100.0 - dbIdleTime * 100.0 /

(double)SysBaseInfo.bKeNumberProcessors + 0.5;
}

// 存储CPU空闲时间和系统时间
// liOldIdleTime = SysPerfInfo.liIdleTime;
// liOldSystemTime = SysTimeInfo.liKeSystemTime;

return (UINT)dbIdleTime;
}