Multitasking (lesson 2) Flashcards
What is multitasking ?
Multitasking is when you have more than one program open and running at the same time.
(The processor allocates a small amount of time to each process and cycles between them. As this happens so quickly, it appears as if multiple programs are executing simultaneously)
What are the steps of memory management ?
1) The operating system handles loading programs from the hard drive into main memory. (RAM)
2) Another smaller program is loaded into memory
3) The first program is closed, removing it from memory and freeing up the space.
Technically, nothing is actually removed from memory – the OS simply marks these areas as empty and available for use.
4) A third program is loaded into memory. This program is bigger, and the OS doesn’t move the programs around in memory – it would take too long.
5) The new program is split
This is called memory FRAGMENTATION
When programs are loaded, the operating system decides:
Where the program is held in memory
As programs are loaded and closed over time, the memory becomes:
Fragmented
If the memory becomes full, _________ will need to be used.
virtual memory
(To make this easier, memory is divided into equal-sized parts called pages.)