Visual Basic App Memory Issue

6 Apr 2005 7:30 PM

bamapookie

I am new to VB, but not new to programming. I am using VB.Net 2003 and
I have written a small app to monitor several running processes and
everything is fine except the memory usage. When the app starts up,
even though there is very little on the form, the memory usage
displayed in task manager jumps to 24MB.
If I minimize the app, usage drops to .6MB. If I then restore the app,
it moves back up to 3-6MB.

Here are a few details about the program:

1. There is a custom control in a separate dll that does the real work.
Each instance of the control monitors 1 app. It takes a small bit of
XML in the form of an XmlElement for initialization. It contains 4
16x16 32bit images, 3 buttons, 2 labels, a tooltip, and a subform for
configuration.
2. The custom controls are stored on a custom tabpage that controls
positioning and size. This tabpage raises a few events that affect the
size of the main form and the form icon.
3. The main form has 4 icons stored in an array and 4 images are stored
in an image list for the tab pages, a menu with 8 entries, and a tab
control.
4. By default, and without an XML file to load from, there are no
custom tab pages or controls loaded, yet the memory issue still occurs.
5. Up until the main form is shown (Form.Show()) and minimized
(Form.WindowState = FormWindowState.Minimized), the memor usage is
between 24 and 30 MB. Once the form is shown and minimized by hand,
the usage drops to 600k. While testing, I wrapped the app in a module
that immediately showed and minimized the form. Doing this
programmatically, the memory usage dropped to 5MB.

Is there anything I can do to reduce the memory footprint of this app?

6 Apr 2005 8:02 PM

Brian Henry

ignore it, thats just the way JIT compilers work with Garbage collection...
the memory system you see in task manager doesn't know how to correctly
display memory usage in a .NET app so you get large ammounts of "allocated"
memory that isn't even in use by the app showing up..

<bamapoo***@gmail.com> wrote in message
Show quoteHide quote

news:1112815821.761943.15320@z14g2000cwz.googlegroups.com...
>I am new to VB, but not new to programming. I am using VB.Net 2003 and
> I have written a small app to monitor several running processes and
> everything is fine except the memory usage. When the app starts up,
> even though there is very little on the form, the memory usage
> displayed in task manager jumps to 24MB.
> If I minimize the app, usage drops to .6MB. If I then restore the app,
> it moves back up to 3-6MB.
>
> Here are a few details about the program:
>
> 1. There is a custom control in a separate dll that does the real work.
> Each instance of the control monitors 1 app. It takes a small bit of
> XML in the form of an XmlElement for initialization. It contains 4
> 16x16 32bit images, 3 buttons, 2 labels, a tooltip, and a subform for
> configuration.
> 2. The custom controls are stored on a custom tabpage that controls
> positioning and size. This tabpage raises a few events that affect the
> size of the main form and the form icon.
> 3. The main form has 4 icons stored in an array and 4 images are stored
> in an image list for the tab pages, a menu with 8 entries, and a tab
> control.
> 4. By default, and without an XML file to load from, there are no
> custom tab pages or controls loaded, yet the memory issue still occurs.
> 5. Up until the main form is shown (Form.Show()) and minimized
> (Form.WindowState = FormWindowState.Minimized), the memor usage is
> between 24 and 30 MB. Once the form is shown and minimized by hand,
> the usage drops to 600k. While testing, I wrapped the app in a module
> that immediately showed and minimized the form. Doing this
> programmatically, the memory usage dropped to 5MB.
>
> Is there anything I can do to reduce the memory footprint of this app?
>

6 Apr 2005 8:28 PM

bamapookie

Is there any easy way to see how much memory is being used?

6 Apr 2005 8:34 PM

Herfried K. Wagner [MVP]

<bamapoo***@gmail.com> schrieb:

>I am new to VB, but not new to programming. I am using VB.Net 2003 and
> I have written a small app to monitor several running processes and
> everything is fine except the memory usage. When the app starts up,
> even though there is very little on the form, the memory usage
> displayed in task manager jumps to 24MB.
> If I minimize the app, usage drops to .6MB. If I then restore the app,
> it moves back up to 3-6MB.

The behavior caused by minimizing a form is not specific to .NET
applications only. It is a feature of the Windows/Explorer shell. If an
application is minimized, Windows removes the working set memory from the
application by calling the Win32 function 'SetProcessWorkingSetSize':

<URL:http://msdn.microsoft.com/library/en-us/dllproc/base/setprocessworkingsetsize.asp>

Windows supposes that minimized applications will not be used for some time
and this memory will be made available to other processes. When restoring
the window the application gets the memory back:

PRB: An Application's Working Set Is Trimmed When Its Top-Level Window Is
Minimized
<URL:http://support.microsoft.com/?scid=kb;EN-US;293215>

This behavior is by design and it doesn't make sense to worry about it.

The Memory Mystery
<URL:http://getdotnetco.web101.discountasp.net/GdncStore/free/Articles/The%20Memory%20Mystery.htm>

Allocation Profiler src
<URL:http://www.gotdotnet.com/Community/UserSamples/Details.aspx?SampleGuid=3254325d-a4aa-4bb3-aa86-c72d5104ec74>

--
M S Herfried K. Wagner
M V P <URL:http://dotnet.mvps.org/>
V B <URL:http://classicvb.org/petition/>