It\'s a good practice to put lots of autoreleased object in an autoreleasepool at loop action. I found someone put the @autoreleasepool in loop but others p
Here is a different approach with Core Data an autoreleasepools:
Testing Core Data with very big hierarchical data sets of Efficiently Importing Data
important for you is the Wrap the contents of the outer loop in an NSAutoreleasePool init/release and NSManagedObjectContext save solution.