1.2 Memory and storage Flashcards
What are the 3 types of secondary storage?
Magnetic
Solid-State
Optical
Why may people choose to buy SSDs over HDDs?
SSD are faster to read/write then HDD… so the person may choose SSD if they want to read/write data quickly,
SSD has no moving parts so it is more portable then a HDD… so the person may choose SSD if they are using a mobile device such as a mobile phone or a laptop,
SSD are also more energy efficient then HDD as they have no moving parts whereas a HDD has moving parts
SSD are robust so they can take more shocks/vibrations then HDD.. they are better for scenarios involving industrial machinery and vehicles
Why may people choose to buy HDDs over SSDs?
HDD usually cost less per GB then SSD so the person may choose to buy an HDD when they want to store lots of data that may not be accessed regularly
Why is having secondary storage beneficial?
Secondary storage is long-term non-volatile so having secondary storage means that data can be stored on it that will be saved when power is lost
What are uses of flash memory?
Solid State Drives (SSD)
Secure Digital (SD) cards
ROM chips
What are properties of Flash memory?
Fast access,
Non-volatile,
Robust, shock resistance
Short lifetime, can only re-write a limited amount of times
What could we do to increase the amount of available memory when memory starts to run out of space?
Terminate processes,
Install more RAM,
Use secondary storage as virtual memory
What are ‘pages’
Split sections on the memory
Explain how virtual memory work?
Virtual memory moves pages between the RAM and the secondary storage
The page on the secondary storage is put into a special file called the pagefile, this means the freed space on the RAM can be used
If we want to use the page again that is in the virtual memory, we move it back to the RAM by swapping it with a page that is already in the RAM that is not being used
What are the different types of primary memory?
Random Access Memory
Read-only Memory
Cache
