I have this reasonably standard ADT in Swift that I use to parse some JSON data which, by all accounts, looks very much like those data structures. The JSON file represents an array of about 155k objects that get parsed into a corresponding [LogRow].
Now, I'm perfectly aware that there is going to be some overhead compared to a plain text representation such as JSON, but what I found is that a JSON file of about 500 MB ends up taking up to 5.5 GB of my computer's memory -- in my book, that's a 10-fold overhead, unless I'm missing something.
I had a look around with Xcode's profiler, but I couldn't see any memory leak. I'm even careful of taking data and decoder into vars so I can nil them and give a nudge to the ARC, but that doesn't seem to work very well, as I assume I'm creating loads of pointers everywhere, so hardly anything gets deallocated.
I had my code checked by people more expert than me with Swift, and they all agreed the code is OK and the overhead is pretty awesome. Can anybody point me towards any docs on the memory requirements of the object model, perhaps.
EDIT For reference, here's what I see in Instruments. He slight drop at the end is when the source file is deallocated (I preallocate it entirely in a string before passing it to the JSONDecoder.
