How do I find a memory leak on my Iphone?

How do I find a memory leak on my Iphone?

To detect memory leaks you should run the app and navigate through all possible flows and open several times the same view controllers, then enter memory graph debugger and look at the memory heap. Look for objects that shouldn’t be in memory, for example: A view controller that is no longer present in the app.

How do you fix a Swift memory leak?

How to eliminate Memory Leaks?

1. Don’t create them. Have a strong understanding of memory management.
2. Use Swift Lint. It is a great tool that enforces you to adhere to a code style and keep rule 1.
3. Detect leaks at run-time and make them visible.
4. Profile the app frequently.
5. Unit Test Leaks with SpecLeaks.

What is a memory leak and how would you handle it?

Memory leak occurs when programmers create a memory in heap and forget to delete it. The consequences of memory leak is that it reduces the performance of the computer by reducing the amount of available memory.

How do instruments detect memory leaks?

Diagnose Memory Leaks Using Xcode Instruments

1. We open the Xcode leaks instrument first and press the record button.
2. When the app automatically launches, we press on the navigate button that presents our leaking view controller.
3. We simply pop it using navigation item’s back button.

What is a memory leak iOS?

A memory leak in iOS is when an amount of allocated space in memory cannot be deallocated due to retain cycles. Since Swift uses Automatic Reference Counting (ARC), a retain cycle occurs when two or more objects hold strong references to each other.

What is a retain cycle?

paul_f. 991●13 ●16. Up vote 1. Retain Cycle is the condition when 2 objects keep a reference to each other and are retained, it creates a retain cycle since both objects try to retain each other, making it impossible to release. Example: A person lives in a department, a department has one person.

What causes Swift memory leak?

Memory leaks in Swift are often the product of a retain cycle, when one object will hold a strong reference to an object that also strongly references the original object. So A retains B and B retains A . These kinds of issues can sometimes be tricky to debug and lead to hard to reproduce crashes.

What happens when memory leak?

A memory leak reduces the performance of the computer by reducing the amount of available memory. Eventually, in the worst case, too much of the available memory may become allocated and all or part of the system or device stops working correctly, the application fails, or the system slows down vastly due to thrashing.

How do you fix memory leaks?

If you have a memory leak and get to the point of almost running out of memory, the normal procedure is to reboot the machine in order to clear out the memory. You can use RAMMap to clear areas of memory negating the need to reboot the machine.

What is a retain cycle Swift?

What are retain cycles and memory leaks? A memory leak in iOS is when an amount of allocated space in memory cannot be deallocated due to retain cycles. Since Swift uses Automatic Reference Counting (ARC), a retain cycle occurs when two or more objects hold strong references to each other.

What is a memory leak in programming?

In computer science, a memory leak is a type of resource leak that occurs when a computer program incorrectly manages memory allocations in such a way that memory which is no longer needed is not released. A memory leak may also happen when an object is stored in memory but cannot be accessed by the running code.

Can memory leak cause crash iOS?

Memory leaks in iOS can be extremely frustrating. While memory leaks alone won’t necessarily cause an application to crash, keeping instances of objects around longer than they should can lead to unintended behaviors. The crash log below is indirectly the result of a memory leak caused by a retain cycle in an iOS app.

How does a retain cycle occur in Swift?

Since Swift uses Automatic Reference Counting (ARC), a retain cycle occurs when two or more objects hold strong references to each other. As a result these objects retain each other in memory because their retain count would never decrement to 0, which would prevent deinit from ever being called and memory from being freed.

What happens when there is a memory leak?

Memory leaks increase the memory footprint incrementally in your app, and when it reaches a certain threshold the operating system (iOS) this triggers a memory warning. If that memory warning is not handled, your app would be force-killed, which is an OOM (Out of memory) crash.

How to prevent memory leaks in Swift closures?

Only capture variables as unowned when you can be sure they will be in memory whenever the closure is run, not just because you don’t want to work with an optional self. This will help you prevent memory leaks in Swift closures, leading to better app performance.

When does arc cause a swift memory leak?

Even though ARC mostly decreased the need to worry about memory management, it can still create Swift memory leaks whenever there are circular references. For example, say that we have a Person class that has a property for an apartment and the Apartment class has a Person property named tenant: