What is the difference between arc automatic reference counting and GC garbage collection )?

ARC rely on a compile time “referenced” objects which make it efficient in a low-power mode environments (Mobile devices). GC rely on a runtime based “reachable” objects which make it efficient in a multi-threaded environment.

What is garbage collection discuss reference counting GC algorithm?

Reference counting GC algorithms associate a reference count with each object. These algorithms consider an object to be alive as long as the number of references to that object is greater than zero. Usually, the runtime stores the reference count in the object header.

How does reference count work?

Reference counting works by counting the number of references to each object. When the reference count drops to zero the object is definitely unreachable and can be recycled.

When do you use reference counting?

1 Answer. Reference counting allows clients of your library to keep reference objects created by your library on the heap and allows you to keep track of how many references are still active. When the reference count goes to zero you can safely free the memory used by the object.

Which is faster garbage collection or reference counting?

Performance wise, if you ask Java developers they say garbage collection is faster; if you ask say Objective-C developers they say reference counting is faster. Studies prove what they want to prove.

Do I need to know how garbage collection works?

There’s no need to worry about memory management because it’s all taken care of for you by reference counting, and this means there’s no need to worry about understanding how garbage collection works. When I heard this I thought to myself, “why would anyone use garbage collection when you can simply use reference counting?”

What is the difference between reference counting and GC?

Reference counting is a form of garbage collection so the question is technically nonsensical. You probably meant to ask for a comparison of reference counting and tracing GC. Reference counting works by counting the number of references to each object. When the reference count drops to zero the object is definitely unreachable and can be recycled.

Why does reference counting not work in Java?

Reference counting will fail to work whenever the data structure contains a cycle of references, so reference counting by itself is not a suitable garbage collection scheme. However, it is a useful technique for dealing with simple objects that don’t refer to other objects, such as int and floats.