iPad app - CALayer makes it very laggy when rotating

Question

Im currently working on an universal app, and in one of my view controllers i have the following xib:

View
 -ImageView
 -TableView
 -ImageView
 -View (called tblviewContainer in the following snippet of code)

In my viewdidload method i have made an layer which i will put on my view(tblviewcontainer) so that some of the top and the bottom of the screen is gradient.

[tblViewContainer addSubview:self.tableView];
[tblViewContainer sendSubviewToBack:self.tableView];

if (!maskLayer)
{
    maskLayer = [CAGradientLayer layer];

    UIColor* outerColorSetup = [UIColor colorWithWhite:1.0 alpha:0.0];
    UIColor* innerColorSetup = [UIColor colorWithWhite:1.0 alpha:1.0];

    CGColorRef outerColor = outerColorSetup.CGColor;
    CGColorRef innerColor = innerColorSetup.CGColor;

    maskLayer.colors = [NSArray arrayWithObjects:
                         (__bridge id )outerColor,
                         (__bridge id)innerColor,
                         (__bridge id)innerColor, 
                         (__bridge id)outerColor, nil];

    maskLayer.locations = [NSArray arrayWithObjects:
                           [NSNumber numberWithFloat:0.01],
                           [NSNumber numberWithFloat:0.04],
                           [NSNumber numberWithFloat:0.8],
                           [NSNumber numberWithFloat:1.0], nil];

    maskLayer.bounds = CGRectMake(0, 0,
                                  self.tableView.frame.size.width,
                                  self.tableView.frame.size.height);

    maskLayer.anchorPoint = CGPointZero;

    tblViewContainer.layer.mask = maskLayer;

}

In my app it is possible to rotate, and when i do that with the layer on, it is very slow/laggy when i rotate (only on ipad 3!).

When i rotate i do the following: (from portrait->landscape)

-(void)willRotateToInterfaceOrientation: (UIInterfaceOrientation)orientation duration:(NSTimeInterval)duration
{
    if (orientation == UIInterfaceOrientationPortrait || orientation == UIInterfaceOrientationPortraitUpsideDown)
    {

    }
    else if(orientation == UIInterfaceOrientationLandscapeLeft || orientation == UIInterfaceOrientationLandscapeRight)
    {
        _landscape = [[ipad_VideoListViewController_Landscape alloc] initWithNibName:@"ipad_VideoListViewController_Landscape" bundle:nil];
        _landscape.scroolViewContentOffset = scroolViewContentOffset;
         [self.view.layer setRasterizationScale:[UIScreen mainScreen].scale];
          self.view.layer.shouldRasterize = YES;


        NSMutableArray *viewCons = [[[self navigationController]viewControllers] mutableCopy];
        [viewCons removeLastObject];
        [viewCons addObject:_landscape];
        [[self navigationController]setViewControllers:viewCons animated:NO];
    }
}

Worst part is it works flawlessly on the ipad 2 with the layer active, but ipad 3 cant seem to handle it. It even seems that the things i do with animation on ipad 2 (which works), cant be handle on the ipad 3. E.g. i made my own tableview header cells / tableview cells, and they also lag if i use them on ipad 3.

Any help would be appreciated!

Answer 1

I added some transparent images instead and its running smooth.

Still, if anyone know why this does not work, i would like to know.

Had to find this solution, because i have a deadline :).

And thanks for the comment Michael!