CPP Memory Management & Performance Optimization

Question 1

What is a memory leak in software applications?

Accepted Answer

Allocated memory that is never freed, causing the program to consume increasing amounts of RAM

Answer

A memory leak occurs when a program allocates heap memory but never releases it, eventually exhausting available memory.

Question 2

What is garbage collection in a managed runtime environment?

Accepted Answer

Automatic identification and freeing of memory no longer referenced by the application

Answer

Garbage collection automates memory reclamation by detecting objects with no live references and freeing their memory.

Question 3

What is the difference between stack and heap memory?

Accepted Answer

Stack memory is automatically managed and stores local variables; heap memory is dynamically allocated and manually managed

Answer

The stack holds local variables with automatic allocation/deallocation per function call, while the heap holds dynamically allocated objects.

Question 4

What does 'Big O notation' measure in algorithm performance?

Accepted Answer

How an algorithm's runtime or space requirements grow relative to input size

Answer

Big O notation describes the upper bound of an algorithm's time or space complexity as a function of input size.

Question 5

What is CPU cache locality and why does it matter for performance?

Accepted Answer

Accessing data that is physically close in memory, improving cache hit rates and reducing access time

Answer

Cache locality means accessing contiguous or nearby memory addresses so data is likely already in the fast CPU cache, reducing costly RAM fetches.

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