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by marvy 4259 days ago
If they only have a gig of RAM, why does iOS bother with 64-bit support at all? Doesn't that increase memory pressure due to all the pointers being twice as big?
1 comments

It's a bit more complicated than that. There's a really good discussion here:

http://www.sealiesoftware.com/blog/archive/2013/09/24/objc_e...

and here:

https://www.mikeash.com/pyblog/friday-qa-2013-09-27-arm64-an...

Basically, as I understand it, 64-bit pointers on iOS can actually act to decrease memory pressure because the extra bits can be used to store object class information that would otherwise have to be stored separately.

Thanks!