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I am using the NSBatchDeleteRequest on a background thread to delete thousands of objects from a SQLite Core Data store. My observation is that in my case it requires about 20 seconds to delete 1000 objects. Is this too slow in comparison to what it should do ?I tried to distribute the work over several threads with no improvement even when using different NSPersistentStoreCoordinators to allow parallel write access to the store. Is there another way to improve this ?