> On Dec 5, 2016, at 4:12 PM, Daryle Walker <dary...@mac.com> wrote: > > For the Swift 3 "Data" type, if I want to represent a multi-gigabyte file, it > won't try to do it all in memory, would it?
The Data type specifically represents in-memory data, so yeah, it would. (Where by “memory” I mean “address space”, which is not at all the same thing as physical RAM on macOS, though it is on iOS. You haven’t specified which platform you’re interested in.) > Or would I have to manage a memory-mapped NSData and somehow connect it to a > Data object? On Mac this would be of limited use; all it changes is that when your data gets paged out it will be written to your custom file instead of the OS’s usual swap file. It probably won’t improve performance although it would help keep the swap file from growing as much. On iOS, however, this is the way to go if you need large amounts of address space. Although I’ve heard that for some reason iOS artificially limits the amount of space you can memory-map. I don’t remember what the limit is, but it’s on the order of 400MB or so; anyone know for sure? (I think there are old threads here about it.) —Jens _______________________________________________ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: https://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
