memory keep on increasing when a opening a same uiviewcontroller again in iphone

I have two uiviewcontroller and i am releasing all the resources in dealloc and setting them to nil in didunload but still when i came across to both viewcontrollers the memory keep on increasing.

I am keeping the track of memory used and free memory from this post

Can anyone suggest why this is happening?

this is the second viewcontroller:

- (void)viewDidUnload {
    adView.delegate = nil;    
    [self setCountDown:nil];    
    [self setUploadPhoto:nil];   
    [self setBackclicked:nil];   
    [self setInfo:nil];   
    [self setCloseButton:nil];   
    [self setHow2usebg:nil];   
    [self setHow2useInstruction:nil];  
    [self setHow2useicon:nil];    
    [self setVc1:nil];   
    [self setVc:nil];   
    adView = nil;   
    [super viewDidUnload];
}

-(void)dealloc
{

    [adView release];
    [closeButton release];
    [how2usebg release];
    [how2useInstruction release];
    [how2useicon release];
    [videoRecorder1 release];
    [uploadPhoto release];
    [countDown release];
    [backclicked release];
    [info release];
    [vc release];
    [talkingImage release];
    [backgroundImage release];
    [super dealloc];
}

I think u are adding a viewcontroller upon another viewcontroller.. like the below line..

[self.view addSubView:yoursecondview];

Create a Appdelegate object and then add the window, instead of self.view

AppDelegate *object=[[UIApplication SharedApplication] delegate];
[self.view removeFromSuperview];
[object.window addSubView:yoursecondview];