This document discusses memory management techniques. It defines memory and the memory hierarchy, including primary and secondary memory. It describes how the memory management unit handles memory by allocating, deallocating, and swapping between main memory and disk. It also discusses paging, fragmentation, defragmentation, and segmentation as memory management techniques.

3. “What goes around comes
around whether you are
giving respect to someone
or deceiving them”

4. Objective
• What is Memory?
• Memory Hierarchy
• Swapping
• Paging Fragmentation
• Defragmentation
• Segmentation

5. What is memory?
Memory store the programs & these programs
are used by CPU for processing.

6. Memory Hierarchy
Primary memory:-
Main memory(Hard disk,RAM)
Connected through data buses to CPU
Expensive & Smaller
Faster
Secondary memory:-
Extrenal Devices(CD , Floppy Disk etc)
Connected through data cables to CPU
Cheaper & larger
Slower

7. Memory Management
It’s a term used to describes how handle the
memory.
MMU(Memory Management Unit)
MMU of the operating system handle the
memory hierarchy.

8. How MMU Work?
• Keep track what part of memory are in use
• Memory Allocate
• Memory Deallocate
• Swapping b/w main memory & Disk

9. Swapping

10. • Paging
• Fragmentation

11. Defragmentation
• Defragmentation is like cleaning
house for your PC, it picks up all of
the pieces of data that are spread
across your hard drive and puts
them back together again.

14. Segmentation
Segmentation is a memory management
technique in which each job is divided
into several segments of different sizes,
one for each module that contains
pieces that perform related functions.