1.1.3 Input, Output And Storage- (c. RAM and ROM)

What are the features of Random Access Memory(RAM)?

1. Volatile:

lose its contents when power is lost

2. Expensive:

more expensive per unit capacity than secondary storage media.

3. Fast:

much faster to access than secondary storage

4. Random Access:

any part of the memory can be accessed non-sequentially and as quickly as any other part of the memory.

What is ROM?

It comes on a small, factory made chip in the motherboard.

What are features of Read Only Memory(ROM)?

1. Non-volatile:

keeps its contents when power is lost.

2. Fast but expensive:

very fast to access.

typically expensive, so tends to be only small.

3. Read only:

-often made from flash memory. This means that its contents cannot be changed easily

-only stores small programs that boots or starts up the computer.

These programs are called the Basic Input Output System (BIOS).:

They usually:

Load an operating system.

Check the system for errors.

Explain why a larger ROM update would not affect performance of a computer.

-Rom is read only and any additional space cannot be written to

-ROM only stores the computers start up instructions which have a finite capacity

What can we do when we run out of space by using RAM?

Purchase and install more RAM so that we can store more data.

This is not always ideal because:

-RAM can be expensive.

-We may only need more memory on a temporary basis

What can we do when we run out of space by using Virtual Memory?

Technique where we use secondary storage as if it were RAM when we run out.

Virtual memory is not always ideal since:

-Virtual Memory can have negative impacts on performance.

-Virtual Memory can have negative impacts on the health of Solid State Disks (SSDs).

-We might have limited space in secondary storage.

What can we do when we run out of space by terminating processes?

1. Each program/process will use a certain amount of memory.

2. By closing some processes that we are not using, we can free the memory that they are using.

3. This is not always possible because we may need all the processes