Use the cpu 100% - multithreading

Question

I need a function that will use my cpu 100% . I have a single core cpu any ideas ?
Does the thread need to be set in high priority ?

Answer 1

A loop (infinite) usually does the job fine:
while true do begin
end;
Obviously forcing the CPU go to 100% without doing anything useful should be done only for academic purposes and on your own hardware and never in any real application that you intend to ship.

Answer 2

For example, by the next thread:
unit Unit2;
interface
uses
Classes;
type
TLoadThread = class(TThread)
public
class var Stop: Boolean;
protected
procedure Execute; override;
public
constructor Create;
end;
implementation
constructor TLoadThread.Create;
begin
inherited Create;
FreeOnTerminate:= True;
end;
procedure TLoadThread.Execute;
begin
repeat until Stop;
end;
end.
A usage example:
type
TForm1 = class(TForm)
Button1: TButton;
Button2: TButton;
procedure Button1Click(Sender: TObject);
procedure Button2Click(Sender: TObject);
end;
var
Form1: TForm1;
implementation
uses Unit2;
{$R *.dfm}
procedure LoadCPU;
begin
TLoadThread.Stop:= False;
TLoadThread.Create;
end;
procedure TForm1.Button1Click(Sender: TObject);
begin
LoadCPU;
end;
procedure TForm1.Button2Click(Sender: TObject);
begin
TLoadThread.Stop:= True;
end;
if your CPU has N cores, click Button1 N times to reach 100% CPU load; no need to increase thread priority.