Table view not working smoothly with SDWebImage - performance

Question

Why isn’t my table view not working smoothly? I use SDWebImage to set the image from a URL. I'm trying to draw 3 images in each row of the table view.
It works fine when arrList is small, but when I increase arrList, it becomes slower and slower (look like a little vibration when I scroll the table view).
This is my code:
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *CellIdentifier = #"CustomCell";
CustomCellTable *cell = (CustomCellTable*) [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil) {
NSArray * nib = [[NSBundle mainBundle] loadNibNamed:#"CustomCellTable" owner:self options:nil];
cell = [nib objectAtIndex:0];
}
[cell setBackgroundColor:brgColor];
// item 1
if ((indexPath.row*3) > arrList.count-1) return cell;
vod *Item = [arrList objectAtIndex:(indexPath.row*3)];
[cell.image1 setHidden:NO];
[cell.image1 setImageWithURL:[NSURL URLWithString:Item.imageURl] placeholderImage:[UIImage imageNamed:#"poster_default.png"]];
[cell makeRating:[Item.rating floatValue] positionOf:14];
// item 2
if ((indexPath.row*3 +1) > arrList.count-1) return cell;
Item = [arrList objectAtIndex:(indexPath.row*3+1)];
[cell.image2 setHidden:NO];
[cell.image2 setImageWithURL:[NSURL URLWithString:Item.imageURl] placeholderImage:[UIImage imageNamed:#"poster_default.png"]];
[cell makeRating:[Item.rating floatValue] positionOf:118];
// item 3
if ((indexPath.row*3 +2) > arrList.count-1) return cell;
Item = [arrList objectAtIndex:(indexPath.row*3+2)];
[cell.image3 setHidden:NO];
[cell.image3 setImageWithURL:[NSURL URLWithString:Item.imageURl] placeholderImage:[UIImage imageNamed:#"poster_default.png"]];
[cell makeRating:[Item.rating floatValue] positionOf:225];
return cell;
}

Answer 1

Look into down sampling the images so you're not storing/loading the large versions of the images while scrolling.
https://github.com/toptierlabs/ImageCacheResize
This library combines SDWebImage with UIImage+Resize. Using it instead of just SDWebImage might help. Specifically use the following method to load the images:
- (void)setImageWithURL:(NSURL *)url andResize:(CGSize)size withContentMode:(UIViewContentMode)mode;