Memory Management Flashcards
1
Q
What is the Memory Manager OS responsible for?
A
- Allocating memory to processes
- Loading and unloading individual processes without impacting others
2
Q
When is memory management used?
A
To ensure RAM is used efficiently and not wasted.
Otherwise RAM would rapidly run out and fill up with unneeded data so no new applications could run
3
Q
2 types of memory management
A
1) Paging
2) Segmentation
4
Q
Paging
A
- Uses fixed size divisions
- Memory is divided physically
- A page table is used to map page location
- Easier for OS to manage pace locations as they can be stored non-contiguously (not touching each other)
5
Q
Segmentation
A
- Uses varying size divisions
- Causes external fragmentation
- Works better contiguously
- Errors can cause memory leakage which could cause the system to crash
6
Q
Similarities between paging and segmentation
A
- Both allow programs to run despite there not being enough memory
- Stored on a disk
- Transferred into memory when needed
7
Q
Differences between paging and segmentation
A
- Pages are fixed size. Segments are different sizes
- Pages are made to fit sections of memory. Segments are complete sections of programs. Pages are physical divisions. Segments are logical divisions
8
Q
When is virtual memory used?
A
When RAM is full to enable applications to continue to run
9
Q
How is data transferred between RAM and VM
A
Data is transferred out of RAM into VM to free up space and then transferred back again when needed
10
Q
Why is VM useful?
A
RAM is much more expensive so VM saves buying more RAM
11
Q
What happens if you over use VM?
A
System slows down
