unit Unit1;
interface
uses
Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
Dialogs, StdCtrls;
type
TPDWord = ^DWORD;
TSystem_Basic_Information =
packed record
dwUnknown1: DWORD;
uKeMaximumIncrement: ULONG;
uPageSize: ULONG;
uMmNumberOfPhysicalPages: ULONG;
uMmLowestPhysicalPage: ULONG;
uMmHighestPhysicalPage: ULONG;
uAllocationGranularity: ULONG;
pLowestUserAddress: Pointer;
pMmHighestUserAddress: Pointer;
uKeActiveProcessors: ULONG;
bKeNumberProcessors: byte;
bUnknown2: byte;
wUnknown3: word;
end;
type
TSystem_Performance_Information =
packed record
liIdleTime: LARGE_INTEGER;
{LARGE_INTEGER}
dwSpare:
array[0..75]
of DWORD;
end;
type
TSystem_Time_Information =
packed record
liKeBootTime: LARGE_INTEGER;
liKeSystemTime: LARGE_INTEGER;
liExpTimeZoneBias: LARGE_INTEGER;
uCurrentTimeZoneId: ULONG;
dwReserved: DWORD;
end;
type
TForm1 =
class(TForm)
Button1: TButton;
Label1: TLabel;
procedure Button1Click(Sender: TObject);
private
{ Private-Deklarationen }
public
{ Public-Deklarationen }
end;
const
SystemBasicInformation = 0;
SystemPerformanceInformation = 2;
SystemTimeInformation = 3;
var
Form1: TForm1;
NtQuerySystemInformation:
function(infoClass: DWORD;
buffer: Pointer;
bufSize: DWORD;
returnSize: TPDword): DWORD;
stdcall =
nil;
liOldIdleTime: LARGE_INTEGER = ();
liOldSystemTime: LARGE_INTEGER = ();
implementation
{$R *.dfm}
function Li2Double(x: LARGE_INTEGER): Double;
begin
Result := x.HighPart * 4.294967296E9 + x.LowPart
end;
procedure GetCPUUsage;
var
SysBaseInfo: TSystem_Basic_Information;
SysPerfInfo: TSystem_Performance_Information;
SysTimeInfo: TSystem_Time_Information;
status: Longint;
{long}
dbSystemTime: Double;
dbIdleTime: Double;
bLoopAborted : boolean;
begin
if @NtQuerySystemInformation =
nil then
NtQuerySystemInformation := GetProcAddress(GetModuleHandle('
ntdll.dll'),
'
NtQuerySystemInformation');
// get number of processors in the system
status := NtQuerySystemInformation(SystemBasicInformation, @SysBaseInfo, SizeOf(SysBaseInfo),
nil);
if status <> 0
then Exit;
// Show some information
with SysBaseInfo
do
begin
ShowMessage(
Format('
uKeMaximumIncrement: %d'#13'
uPageSize: %d'#13+
'
uMmNumberOfPhysicalPages: %d'+#13+'
uMmLowestPhysicalPage: %d'+#13+
'
uMmHighestPhysicalPage: %d'+#13+'
uAllocationGranularity: %d'#13+
'
uKeActiveProcessors: %d'#13'
bKeNumberProcessors: %d',
[uKeMaximumIncrement, uPageSize, uMmNumberOfPhysicalPages,
uMmLowestPhysicalPage, uMmHighestPhysicalPage, uAllocationGranularity,
uKeActiveProcessors, bKeNumberProcessors]));
end;
bLoopAborted := False;
// get new system time
status := NtQuerySystemInformation(SystemTimeInformation, @SysTimeInfo, SizeOf(SysTimeInfo), 0);
if status <> 0
then Exit;
// get new CPU's idle time
status := NtQuerySystemInformation(SystemPerformanceInformation, @SysPerfInfo, SizeOf(SysPerfInfo),
nil);
if status <> 0
then Exit;
// if it's a first call - skip it
if (liOldIdleTime.QuadPart <> 0)
then
begin
// 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 / SysBaseInfo.bKeNumberProcessors + 0.5;
// Show Percentage
Form1.Label1.Caption := FormatFloat('
CPU Usage: 0.0 %',dbIdleTime);
Application.ProcessMessages;
// Abort if user pressed ESC or Application is terminated
bLoopAborted := (GetKeyState(VK_ESCAPE)
and 128 = 128)
or Application.Terminated;
end;
// store new CPU's idle and system time
liOldIdleTime := SysPerfInfo.liIdleTime;
liOldSystemTime := SysTimeInfo.liKeSystemTime;
end;
procedure TForm1.Button1Click(Sender: TObject);
begin
GetCPUUsage
end;
end.