Memory Management

Question 1

What is the primary function of memory management in Layer 3?

Answer 1

It ensures that processes and data are in primary memory (PM) for operation, manages competition for finite memory resources, and protects co-resident processes from one another

Question 2

Define Virtual Address

Answer 2

A virtual address is relative to the start of a process’s address space and not the actual physical memory location

Question 3

What is the difference between compile-time, load-time, and execution-time binding?

Answer 3

• Compile-time, memory addresses are fixed at compile time
• Load-time, addresses are determined when the program loads into memory
• Execution-time, addresses can change dynamically during execution

Question 4

What are the three main goals when multiple programs share memory?

Answer 4

Transparency, safety, and efficiency

Question 5

What is the difference between static and dynamic relocation?

Answer 5

• Static Relocation, memory mapping is done before or during process loading and cannot be moved afterward
• Dynamic Relocation, memory mapping is done at runtime, allowing processes to move freely in memory

Question 6

What is external fragmentation?

Answer 6

It occurs when total memory is sufficient to satisfy a request, but it’s not contiguous

Question 7

What are the advantages of paging?

Answer 7

• Simplifies memory allocation
• Eliminates external fragmentation
• Allows processes to use memory efficiently through logical segmentation

Question 8

How does segmentation differ from paging?

Answer 8

• Segmentation divides memory into variable-sized logical segments
• Paging divides memory into fixed-sized blocks and removes the need for contiguous memory allocation