What are stack and heap in the context of memory management? Who has access to the stack and heap? Why is the stack faster?

Stack and heap are two main ways of managing memory in programs.

Stack is a memory area where local variables and function call contexts are stored. Access to the stack is only available to the current thread of execution (goroutine in Go). The stack operates on a LIFO (last in, first out) principle. It is very fast because memory allocation and deallocation are simply done by moving the stack pointer.

Heap is a memory area for dynamic allocation, where objects with a long lifetime are stored, for example, created via new or make in Go. All threads have access to the heap, but memory management is more complex: allocation and garbage collection require additional overhead.

Why is the stack faster?

• Memory allocation on the stack is just moving the pointer, without searching for a free block.
• Memory is automatically freed when exiting a function.
• There is no need for a garbage collector for the stack.

In Go, the goroutine stack grows dynamically, but operations on the stack still remain very fast compared to the heap.