unit MemForm;

interface

uses
  Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,
  Grids, ExtCtrls, StdCtrls;

type
  TForm1 = class(TForm)
    StringGrid1: TStringGrid;
    Timer1: TTimer;
    StringGrid2: TStringGrid;
    BtnString: TButton;
    BtnStringList: TButton;
    BtnForm: TButton;
    BtnBigAlloc: TButton;
    BtnSmallAlloc: TButton;
    procedure FormCreate(Sender: TObject);
    procedure Timer1Timer(Sender: TObject);
    procedure BtnStringClick(Sender: TObject);
    procedure BtnStringListClick(Sender: TObject);
    procedure BtnFormClick(Sender: TObject);
    procedure BtnSmallAllocClick(Sender: TObject);
    procedure BtnBigAllocClick(Sender: TObject);
  private
    procedure UpdateStatus;
  public
    s: string;
    sl: TStringList;
    f: TForm;
  end;

var
  Form1: TForm1;

implementation

{$R *.DFM}

procedure TForm1.UpdateStatus;
var
  MemStatus: TMemoryStatus;
  HeapStatus: THeapStatus;
begin
  MemStatus.dwLength := sizeof(TMemoryStatus);
  GlobalMemoryStatus(MemStatus);
  with MemStatus do
  begin
    // load
    StringGrid1.Cells[1, 0] := IntToStr(dwMemoryLoad) + '%';

    // RAM (total, free, load)
    StringGrid1.Cells[1, 1] := FloatToStrF(
      dwTotalPhys / 1024,
      ffNumber, 20, 0) + ' Kbytes';
    StringGrid1.Cells[1, 2] := FloatToStrF(
      dwAvailPhys / 1024,
      ffNumber, 20, 0) + ' Kbytes';
    StringGrid1.Cells[1, 3] := IntToStr(100 -
      dwAvailPhys div (dwTotalPhys div 100)) + '%';

    // page file (total, free, load)
    StringGrid1.Cells[1, 4] := FloatToStrF(
      dwTotalPageFile / 1024,
      ffNumber, 20, 0) + ' Kbytes';
    StringGrid1.Cells[1, 5] := FloatToStrF(
      dwAvailPageFile / 1024,
      ffNumber, 20, 0) + ' Kbytes';
    StringGrid1.Cells[1, 6] := IntToStr(100 -
      dwAvailPageFile div (dwTotalPageFile div 100)) + '%';

    // page file (total, used, free)
    StringGrid1.Cells[1, 7] := FloatToStrF(
      dwTotalVirtual / 1024,
      ffNumber, 20, 0) + ' Kbytes';
    StringGrid1.Cells[1, 8] := FloatToStrF(
      dwAvailVirtual / 1024,
      ffNumber, 20, 0) + ' Kbytes';
    StringGrid1.Cells[1, 9] := FloatToStrF(
      (dwTotalVirtual - dwAvailVirtual) / 1024,
      ffNumber, 20, 0) + ' Kbytes';
  end; // with MemStatus

  HeapStatus := GetHeapStatus;
  with HeapStatus do
  begin
    StringGrid2.Cells[1, 0] := FloatToStrF(
      TotalAddrSpace div 1024,
      ffNumber, 20, 0) + ' Kbytes';
    StringGrid2.Cells[1, 1] := FloatToStrF(
      TotalUncommitted div 1024,
      ffNumber, 20, 0) + ' Kbytes';
    StringGrid2.Cells[1, 2] := FloatToStrF(
      TotalCommitted div 1024,
      ffNumber, 20, 0) + ' Kbytes';
    StringGrid2.Cells[1, 3] := FloatToStrF(
      TotalFree div 1024,
      ffNumber, 20, 0) + ' Kbytes';
    StringGrid2.Cells[1, 4] := FloatToStrF(
      TotalAllocated div 1024,
      ffNumber, 20, 0) + ' Kbytes';
    StringGrid2.Cells[1, 5] := IntToStr(
      TotalAllocated div (TotalAddrSpace div 100)) + '%';
    StringGrid2.Cells[1, 6] := FloatToStrF(
      FreeSmall div 1024,
      ffNumber, 20, 0) + ' Kbytes';
    StringGrid2.Cells[1, 7] := FloatToStrF(
      FreeBig div 1024,
      ffNumber, 20, 0) + ' Kbytes';
    StringGrid2.Cells[1, 8] := FloatToStrF(
      Unused div 1024,
      ffNumber, 20, 0) + ' Kbytes';
    StringGrid2.Cells[1, 9] := FloatToStrF(
      Overhead div 1024,
      ffNumber, 20, 0) + ' Kbytes';
  end;
end;

procedure TForm1.FormCreate(Sender: TObject);
begin
  StringGrid1.Cells[0, 0] := 'Memory load';
  StringGrid1.Cells[0, 1] := 'Physical memory';
  StringGrid1.Cells[0, 2] := 'Free physical memory';
  StringGrid1.Cells[0, 3] := 'RAM load';
  StringGrid1.Cells[0, 4] := 'Maximum size of paging file';
  StringGrid1.Cells[0, 5] := 'Available in paging file';
  StringGrid1.Cells[0, 6] := 'Paging file load';
  StringGrid1.Cells[0, 7] := 'Virtual address space';
  StringGrid1.Cells[0, 8] := 'Free in address space';
  StringGrid1.Cells[0, 9] := 'Used address space';

  StringGrid2.Cells[0, 0] := 'Available address space ';
  StringGrid2.Cells[0, 1] := 'Uncommitted portion';
  StringGrid2.Cells[0, 2] := 'Committed portion';
  StringGrid2.Cells[0, 3] := 'Free portion';
  StringGrid2.Cells[0, 4] := 'Allocated portion';
  StringGrid2.Cells[0, 5] := 'Address space load';
  StringGrid2.Cells[0, 6] := 'Total small free blocks';
  StringGrid2.Cells[0, 7] := 'Total big free blocks';
  StringGrid2.Cells[0, 8] := 'Other unused blocks';
  StringGrid2.Cells[0, 9] := 'Total overhead';

  UpdateStatus;
end;

procedure TForm1.Timer1Timer(Sender: TObject);
begin
  UpdateStatus;
end;

procedure TForm1.BtnStringClick(Sender: TObject);
begin
  // 10 megabytes
  SetLength(s, 10000000);
  UpdateStatus;
end;

procedure TForm1.BtnStringListClick(Sender: TObject);
var
  I: Integer;
begin
  sl := TStringList.Create;
  // add one thousand strings
  for I := 0 to 1000 do
    sl.Add('hello');
  // destroy some of them
  for I := 300 downto 1 do
    sl.Delete(I * 3);
  UpdateStatus;
end;

procedure TForm1.BtnFormClick(Sender: TObject);
var
  I: Integer;
begin
  // create ten forms
  for I := 1 to 10 do
    F := TForm.Create(Application);
  UpdateStatus;
end;

procedure TForm1.BtnSmallAllocClick(Sender: TObject);
var
  P: Pointer;
begin
  GetMem(P, 100);
  Integer(P^) := 10;
  UpdateStatus;
end;

procedure TForm1.BtnBigAllocClick(Sender: TObject);
var
  P: Pointer;
begin
  GetMem(P, 100000);
  Integer(P^) := 10;
  UpdateStatus;
end;

end.