SLR 4 - Systems Software Flashcards
Why do we need an operating system?
Provide an interface between user and hardware, allowing the user to interact with the system.
Name 3 functions of the Operating System.
. File Management
. Application Software
. Memory Management
. Hardware
. User
. Memory Management
What is multitasking and how does it work?
When you have more tha one program open and running at the same time.
The CPU allocatesa a small amount of time to each process and cycles between them, making it appear as if the two are executing simultaneously.
What is processor management?
Deciding what process to execture next.
Handling interrupts
What is peripheral management?
Dealing with I/O requests, using drivers to communicate with hardware
Name 6 utility programs. (ABCDEF)
Antivirus
Backup
Compression
Defragmentation
Encryption
File management
What is memory management?
Loading programs, using RAM efficiently, the use of virtual memory and when to use paging or segmentation.
What is paging?
Paging is when the task is split into physical divisions, each being the same size.
What is segmentation?
Logical divisions of programs, not all the same size, can change depending on free space in RAM.
Positive and negative of Paging?
Benefits:
enables use of virtual memory
Negative:
Can lead to internal fragmentation
Positive and negative of segmentation?
Benefit:
Allows for efficient memory access
Negative:
Can lead to external fragmentation
What is an interrupt?
A signal for the processor to stop its current task and perform a different higher priority one.
Two types of interrupts?
Hardware/ Software interrupts
What is a scheduling algorithm?
An algorithm that decided what tasks to process, for how long, and what order.
What is preemptive scheduling?
Allocates CPU for a specific time to process.
