Stack vs Heap Memory

Updated March 28, 2023

Difference Between Stack vs Heap Memory

What is Stack Memory: The allocation that takes place on contiguous memory blocks. We call it Stack memory assignment since the assignment takes place in the function call stack. The memory to be assigned is known for compiling, and when a feature is called, their variables will be assigned memory to the stack. And once the function call has been completed, the memory is allocated to the variables. All of this takes place with predefined compiler routines. Programmers need not think about allocating stack variables for memory and relocating them.

What is Heap Memory: The heap is a buffer for global variables to be saved by programming languages. All global variable is stored in heap memory space by default. This facilitates the allocation of dynamic memory. The memory is reserved when the programmers execute instructions. Notice that the heap name has nothing to do with the structure of the heap data. It is called a heap as the programmers can allocate and de-allocate a stack of memory space.

Head to Head Comparison between Stack vs Heap Memory (Infographics)

Below are the top 5 comparisons between Stack vs Heap Memory:

Key differences between Stack vs Heap Memory

Let us discuss some key differences between Stack vs Heap Memory in the following points:

1. Stack is a linear data structure, while Heap is a structure of the hierarchical data.
2. Stack memory can never be fragmented, while the heap memory can be fragmented by assigning memory blocks and firing them up.
3. Stack will only handle local variables, while Heap allows you to access global variables.
4. Could not resize the stack variables but can resize the heap variables.
5. A contiguous block is assigned to the stack memory, while Heap is assigned to a random order.
6. Stack requires no variables to be deallocated while deallocation of Heap variables is necessary.
7. The assignment and the distribution are rendered through the compiler instructions, while the programmer allocates and dislocates Heap.
8. Stack frame access is better than the Heap Frame since the stack has a small memory area and is cache-friendly, and when it is spread around the memory, more cache errors are triggered.

Comparison Table of Stack vs Heap Memory

The table below summarizes the comparisons between Stack vs Heap Memory:

Stack Memory	Heap Memory
A stack has a linear data type structure.	A Heap has a Hierarchical Data structure.
The stack has high-speed Access.	As compare to stack, Heap has slower speed access.
OS efficiently manages space so that memory is never fragmented.	Not used as efficiently as Heap Space. Memory can be broken down as first assigned and then freed memory blocks.
Stack gives local variable access.	Heap allows you to access a variable globally.
Operating system dependent stack size limits.	Heap has no specific memory size limit.
In stock, we can’t resize the variables.	In a heap, we can resize the variables.
Memory is assigned in a contiguous block manner.	In a heap, memory is allocated in a random manner.
In stack, compiler instructions are automatically used.	In a heap, a compiler is done manually.
The cost of the stack is less.	The cost of the Heap is more than the stack.
A stack can be implemented by dynamic memory and Linked list based on a simple array in three ways.	You can use an Array and tree to implement the heap.
The flexibility of the size is fixed.	The flexibility of the heap can resized.
Stack access time is very faster as compared to the heap.	Heap access time is slower as compared to Stack.

Advantages & Disadvantages of Stack Memory

Below are the advantages and disadvantages of stack Memory:

Advantages:

1. It helps in controlling memory is allocation and deallocation.
2. Stack automatically cleans up the object.
3. Stack memory can not be corrupted easily.

Disadvantages:

1. Stack memory is minimal.
2. Creating too many objects on the stack can cause a stack overflow.
3. In stack memory, Random access is not possible.

Advantages & Disadvantages of Heap Memory

Below are the advantages and disadvantages of heat Memory:

Advantage:

1. Heap finds the greatest and minimum number.
2. Heap method used in the Priority Queue.
3. Heap allows accessing variables globally.
4. In heap memory, the Garbage collection feature helps to free the memory used by the object.

Disadvantages:

1. It can provide the maximum memory an OS can provide.
2. It takes more time to compute.
3. In heap memory, Memory management is more complicated.
4. Execution time is more in heap memory.

Recommended Articles

This is a guide to Stack vs Heap Memory. Here we discuss the Stack vs Heap Memory key differences with infographics and comparison table. You may also have a look at the following articles to learn more –

1. Stack vs Queue
2. What is Heap Memory?
3. Heap Sort in C++
4. Stack Class in Java