On 23 Oct 2012, at 11:21, Ulf Dunkel <dun...@calamus.net> wrote: > I wonder if this issue is created by our app or if it is inherent in Mac > OS X: > > Our app creates documents which can contain various content per document > page, e.g. PDF files. Assume you have created a document with 64 pages, > each of them contains a full-page PDF content. The document file's > "weight" is about 1 GB when it is saved. > > When users try to reload the document on a Mac with 4 GB RAM, it cannot > be opened, because of a lack of memory.
Important bit you haven't told us: is your app 32bit, 64bit, or both? > Tracking the allocations with > Instruments, I can see strange things happen: > > - The app itself consumes about 300 MB RAM. > - The document is loaded in several steps, where the first step > allocates the document size with -[NSData(NSData) initWithContentsOfFile:]. > - Then the RAM for page content files (the PDFs) is allocated and the > relevant PDF is being loaded - but: > > - The first PDF load process allocates additional RAM for the first PDF. > - The 2nd PDF allocates additional RAM for the 1st and 2nd PDF. > - The 3rd PDF allocates additional RAM for the 1.-3. PDF. > - Etc. > > So this procedure sums up to about 3.5 GB RAM which of course is > followed by an exception. > > On bigger machines, the additional RAM for the PDFs is deallocated after > the document has been loaded successfully. > > Is this a wanted behavior of Mac OS X, or are we able to control how > much RAM is being allocated in the document load process? You have very fine-grained control available to you. Read up on the document architecture and the different NSDocument methods you can override. _______________________________________________ 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
