call stack vs heap

Question 1

Call stack

Answer 1

• Data structure for managing method calls
• Keeps track of sequence of function calls
• When a method call is added to stack, it’s variable(s) memory gets allocated to the stack as well
• When the method call is over, the variable(s) memory gets de-allocated

Question 2

Heap

Answer 2

• Region of memory used for dynamic memory allocation
• Objects created on heap persist beyond the scope of methods or functions that created them
• They can be accessed by multiple parts of your program

Question 3

Heap - reference types

Answer 3

• Reference types (such as objects, arrays, etc.) are typically allocated on the heap
• The memory for these objects are managed by the .NET runtime’s garbage collector -> which determines when objects are no longer needed -> then reclaims their memory

Question 4

Summary

Answer 4

• Call stack is mechanism for managing execution flow and local variables during method calls
• Heap is region of memory used for dynamic memory allocation where objects with longer lifetimes are stored

Question 5

How arrays are accessed in memory

Answer 5

• Reference type arrays (such as objects, strings, or instances of classes) are allocated on the heap
• Value type arrays (such as integers, doubles, or structs):

Allocated on stack if the variable is local
Allocated on heap if the variable is created within a class

Question 6

How arrays are stored in memory

Answer 6

• Adjacent blocks of memory stored sequentially
• Depending on the data type, allocates a block of memory of that data types size
• Base address of array is where the first element is stored