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Amount of virtual memory available?

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eddie-jdp

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Amount of virtual memory available?

Dec 21st, 2006

Hi all,

I am new to windows programming. I am currently using Delphi. Is there a way to tell how much total memory (including virtual memory) is currently available on a computer.

As far as I am aware... Delphi programs start out automatically with an address space of 1 or 2 megs but more memory is automatically made available as needed by the program up until the point where the computer runs out of virtual memory.

So basically the question is...

Is there a delphi function or a win32 function that returns the amount of virtual memory that is currently available.

Any ideas?

Thanks

Eddie

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Ancient Dragon Ancient Dragon is offline

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Re: Amount of virtual memory available?

Dec 21st, 2006

GetSystemInfo()

Don't PM me with questions -- you might get a nasty PM in response. If you have a question then post it in one of the forums.

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eddie-jdp

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Re: Amount of virtual memory available?

Dec 22nd, 2006

Ancient Dragon, thank you so much for your response. I'll have to go away and read up about the function and the SYSTEM_INFO structure that it uses.

I'll confess that at this point, I don't know how to turn the results from a populated SYSTEM_INFO structure into the data I am looking for (i.e. is it related to the page size or the minimum and maximum application addresses. I'll see if I can figure it out. Thank you so much for pointing me in the right direction. If you could be even a bit more explicit as to how to use the SYSTEM_INFO to get an Integer or Long (or Int64 or whatever) that reflects how much virtual memory can still be assigned to running programs, I would definitely appreciate the extra help. In the mean time... I'll try and figure it out.

Thanks once again.

Eddie

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radu84

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Re: Amount of virtual memory available?

Dec 22nd, 2006

To retrieve the current memory status, you can use the GlobalMemoryStatus() function. The TMemoryStatus contains several fields indicating the status of the memory: .dwMemoryLoad: Total memory used in percentage (%)
. .dwTotalPhys: Total physical memory in bytes.
.dwAvailPhys: Physical memory left in bytes.
.dwTotalPageFile: Total page file in bytes.
.dwAvailPageFile

age file left in bytes.
.dwTotalVirtual: Total virtual memory in bytes.
.dwAvailVirtual: Virtual memory left in bytes.

Before presenting the memory values, convert them into giga, mega or kilobytes.

 Help with Code Tags 
 Pascal and Delphi Syntax (Toggle Plain Text) 
var
   Status : TMemoryStatus;
begin
   Status.dwLength := sizeof( TMemoryStatus ) ;
   GlobalMemoryStatus( Status ) ;
var
   Status : TMemoryStatus;
begin
   Status.dwLength := sizeof( TMemoryStatus ) ;
   GlobalMemoryStatus( Status ) ;

and using systeminfo

 Help with Code Tags 
 Pascal and Delphi Syntax (Toggle Plain Text) 
procedure TForm1.Button1Click(Sender: TObject) ;
var MemoryStatus: TMemoryStatus;
begin
  Memo1.Lines.Clear;
  MemoryStatus.dwLength := SizeOf(MemoryStatus) ;
  GlobalMemoryStatus(MemoryStatus) ;
  with MemoryStatus do begin
    Memo1.Lines.Add(IntToStr(dwLength) +
      ' Size of ''MemoryStatus'' record') ;
    Memo1.Lines.Add(IntToStr(dwMemoryLoad) +
      '% memory in use') ;
    Memo1.Lines.Add(IntToStr(dwTotalPhys) +
      ' Total Physical Memory in bytes') ;
    Memo1.Lines.Add(IntToStr(dwAvailPhys) +
      ' Available Physical Memory in bytes') ;
    Memo1.Lines.Add(IntToStr(dwTotalPageFile) +
      ' Total Bytes of Paging File') ;
    Memo1.Lines.Add(IntToStr(dwAvailPageFile) +
      ' Available bytes in paging file') ;
    Memo1.Lines.Add(IntToStr(dwTotalVirtual) +
      ' User Bytes of Address space') ;
    Memo1.Lines.Add(IntToStr(dwAvailVirtual) +
      ' Available User bytes of address space') ;
   end;
end;
procedure TForm1.Button1Click(Sender: TObject) ;
var MemoryStatus: TMemoryStatus;
begin
  Memo1.Lines.Clear;
  MemoryStatus.dwLength := SizeOf(MemoryStatus) ;
  GlobalMemoryStatus(MemoryStatus) ;
  with MemoryStatus do begin
    Memo1.Lines.Add(IntToStr(dwLength) +
      ' Size of ''MemoryStatus'' record') ;
    Memo1.Lines.Add(IntToStr(dwMemoryLoad) +
      '% memory in use') ;
    Memo1.Lines.Add(IntToStr(dwTotalPhys) +
      ' Total Physical Memory in bytes') ;
    Memo1.Lines.Add(IntToStr(dwAvailPhys) +
      ' Available Physical Memory in bytes') ;
    Memo1.Lines.Add(IntToStr(dwTotalPageFile) +
      ' Total Bytes of Paging File') ;
    Memo1.Lines.Add(IntToStr(dwAvailPageFile) +
      ' Available bytes in paging file') ;
    Memo1.Lines.Add(IntToStr(dwTotalVirtual) +
      ' User Bytes of Address space') ;
    Memo1.Lines.Add(IntToStr(dwAvailVirtual) +
      ' Available User bytes of address space') ;
   end;
end;

try to understand this and i'm suggesting you to start reading about API and WinApi.

best regards,

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eddie-jdp

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Re: Amount of virtual memory available?

Dec 22nd, 2006

I just wanted to say a quick thank you for the replies to this thread. I really appreciate them. Radu84, I haven't even had a chance to read your post at this point. The reason for this is that I just received word this morning that there has been a death in my immediate family. I will be travelling abroad and don't expect to have internet access for about a week.

I'll take up the work I was trying to do when I get back early in January. I just wanted to let you guys know... that my lack of response wasn't due to any unappreciation of your help. I appreciate the time and effort you have given in helping me with my question.

Therefore... please know that any lack of further responses from me for just over a week is due to know lack in appreciation.

Sincerely.

Eddie

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eddie-jdp

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Re: Amount of virtual memory available?

Jan 2nd, 2007

Hi guys,

I'm now back from being with the family. Radu84, I've now had a chance to read your post. The 'dwAvailVirtual' field of the TMemoryStatus object/structure sounds like EXACTLY what I want. I'll go and try it out.

Thanks Acient Dragon and Radu84 for your responses.

Best wishes and Happy New Year.

Eddie