VB.NET Memory Management

Question

I have a project that consists of about 30 forms. I go from form to form and everytime i create a form I set it to Nothing and when I close the form I say Me.Dispose(). I also have a database connection which I also say .Dispose() when finished. Unfortunately the memory keeps increasing everytime I open a new form even though the previous form closes. Also if I say something = Nothing then the garbage collector should take care of it right? Thanx

saphiroth42 · Answer

It seems to work very well. I hope there will to no side affects from this. Thanks a lot.

vidhya_bala2003 · Answer

Hi saphiroth Actually i also had the same problem. My project is heavier having more than 110 forms. I also in search of a solution for more than 1 month. i have tried various methods but in vain. At last i tried this mtd and i haven't experienced any performance degrade by using this method. Try out and tell if u face any problem. Chk out this url for more info http://addressof.com/blog/archive/2003/11/19/281.aspx

saphiroth42 · Answer

Again I want to say thanks. How did u find this method? Is it safe to use through out every form? What I did is make a new class and put that function in the class. So I create an instance of the class and call this function to clear out RAM. I hope this is ok to do.

saphiroth42 · Answer

nevermind I read up on the SetProcessWorkingSetSize. Thank you for your help.

saphiroth42 · Answer

I don't clearly understand what this does or how it works. How does it help memory management?

vidhya_bala2003 · Answer

Have you tried using the SetProcessWorkingSetSize Win32 API Function Form1.vb Private Sub Buttonopen_Click(ByVal sender As System.Object ByVal e As System.EventArgs) Handles Button1.Click Dim frm2 As New Form2() frm2.MdiParent = Me frm2.Dock = DockStyle.Fill frm2.Show() frm2.BringToFront() End Sub Form2.vb Private Declare Function SetProcessWorkingSetSize Lib kernel32.dll (ByVal hProcess As IntPtr ByVal dwMinimumWorkingSetSize As Int32 ByVal dwMaximumWorkingSetSize As Int32) As Int32 Public Function SaveMemory() As Int32 Return SetProcessWorkingSetSize(Diagnostics.Process.GetCurrentProcess.Handle -1 -1) End Function 'Form Close Private Sub Buttonclose_Click(ByVal sender As System.Object ByVal e As System.EventArgs) Handles BtnCancel.Click SaveMemory() Me.Close() End Sub

MythicalMe · Answer

Not necessarily. Garbage collection occurs when an object tries to allocate memory for a new object and the heap has no free memory. So memory allocated may not be collected if the apllication doesn't create many objects. Further it can take up to two collection cycles before an object's memory allocation is actually released back to the pool. When memory is collected the object's Finalize method is called and then the collector frees the memory. If you need to get memory back to the heap faster you can call GC.Collect yourself. If you do so you should follow it up with a GC.WaitForPendingFinalizers call. There is a slight performance hit in doing this.