Virtual Memory Flashcards
All 6 cards in this deck
What is virtual memory?
The use of secondary storage, such as a hard disk, as extra primary memory when RAM is insufficient.
What is the name of the process of transferring data between RAM and the hard disk when using virtual memory?
Swapping.
What are the steps showing how virtual memory works when RAM becomes full?
e.g. opening another program when RAM is already full
- Data in RAM not currently being used is transferred to the hard disk.
- The freed RAM space is used by the new program.
- When the swapped-out data is needed again, other unused data is moved to disk and it is swapped back into RAM.
True or false? Using virtual memory makes a computer run faster.
False. It runs slower, because the processor must wait while data is swapped to and from the slower secondary storage.
How can a computer's need to use virtual memory be reduced?
By increasing the amount of RAM, so it is less likely to become full.
Give two reasons why an embedded system might not need virtual memory.
e.g. a car's 'Follow Me' distance-keeping system
It only stores a few specific items in RAM, so is unlikely to run out of RAM; only one/few programs run at a time (no memory-intensive tasks) and the RAM is designed to meet the system's requirements.