CODEWITHSUNDEEP
objective-ciosmemory-managementautomatic-ref-counting
Alessandro
Alessandro

Reputation: 4110

ARC reference counting dealloc, and release

I am getting a bit confused. I am creating an app with storyboard, and running it on iPad 1. the application uses a lot of memory, so reached the 120mb, crashes. accordingly to what I have understood to remove this problem you need to release, dealloc... the point is that with ARC this should be automatic. In fact if I add for e.g.: [label1 release]; it gives me an error. But this ARC automatic release and dealloc does not seem to work! Is this because there are different ways to release with ARC??

enter image description here

Upvotes: 2

Views: 2803

Answers (3)

cesarislaw
cesarislaw

Reputation: 1599

You don't need to manually retain/release/autorelease with ARC. However if you have active references to a lot of unused objects they will still remain in memory. Profile your app with Instruments and it will show you how many objects you're creating of each class and how much memory they're consuming.

With ARC you still need to think about memory usage you just don't need to worry as much about memory leaks.

NSObject *bigMemObj = [[BigMemClass alloc] init];
//This creates the object in memory. In both arc and manual counting the retain count is 1

//Do stuff

//Prior to ARC you would have had to call [bigMemObj release]; before setting the variable to nil
bigMemObj = nil
//With ARC you don't have to do anything. The compiler inserts the release at compile time

Also read the documentation on declaring iVars __strong vs __weak.

Without looking at your code it's hard to identify what is consuming all the memory but hopefully that should help you determine where to start looking.

Upvotes: 4

leanne
leanne

Reputation: 8749

I can't vote this back up, otherwise I would. I think Alessandro is asking about ARC vs using release and dealloc, not about what he's loading!

So, Alessandro, your understanding is correct that with ARC you don't release or dealloc. Therefore, those won't work if you're using ARC. Also, there is no alternative to release/dealloc, since ARC doesn't use it.

My suggestion would be to look at what you're using in the app that is taking up all this memory. Do you have a large number of pictures, for example, that are very large? Keep any graphics as small as possible, matching the resolution of the iPad. Especially the iPad 1, which doesn't have the "retina display".

You can use Autorelease pools in ARC. Here is some documentation on when to use them: NSAutoreleasePool Class Reference Advanced Memory Management Programming Guide: About Memory Management

Upvotes: 0

AMayes
AMayes

Reputation: 1767

You should implement @autoreleasePool{} inside each method. In essence, each method will look like the following:

-(void)methodName{
@autoreleasePool{
//do method stuff
}
}

This will ensure that, upon exiting the autoreleasePool, memory is properly released.

Upvotes: 0

Related Questions