What OSs do
Interrupts
Operating-System Operations
Operating Systems in Computing Environments
???
100
Executing user programs and making solving user
problems easier, make the computer system convenient to use, and using the computer hardware in an efficient manner are ALL goals of this program.
What is an operating system.
Operating System: A program that acts as an intermediary between a user of a computer and the computer hardware. The operating system is a resource allocator and control program making efficient use of HW and managing execution of user programs
100
a software-generated interrupt caused either by an error or a user request.
What is a trap?
100
The main difficulty for programmers writting an OS for a real-time environment.
What is meeting time constraints?
100
Any mechanism for controlling the access of processes or users to the resources defined by a computer system. This mechanism must provide means to specify the controls to be imposed and to enforce the controls.
(Page 33).
What is protection?
200
The strategy of having the CPU switch jobs so frequently that users can interact with each job while it is running, creating interactive computing
What is time sharing?
200
To prevent a lost interrupt, incoming interrupts are [BLANK] while another interrupt is being processed.
What is disabled?
200
What is the goal of multiprogramming?
What is keep CPU busy?
200
a collection of physically separate, possibly heterogeneous computer systems that are networked to provide users with access to the various resources that the system maintains.
What is a distributed system?
300
This instruction is only executable in kernel mode.
What are priveledged instructions?
300
The CPU has limited capability in this mode, thereby enforcing the protection of critical resources.
What is user mode?
300
The mechanisms in place to defend a system from external and internal attacks.
What is security?
400
When does CPU check for interrupts?
What is between instructions?
400
When two or more components need to exchange data and the components perform transfers at differing speeds, this memory component can solve the transfer problem by providing a buffer of intermediate speed between the components.
Whta is cache memory?
Cache memory is a small-sized type of volatile computer memory that provides high-speed data access to a processor and stores frequently used computer programs, applications and data
400
This type of storage is fast to access, has small capacity, and is volatile (loses its content when power is turned off or otherwise lost).
*Volatile storage is often reffered to simply as memory.
What is primary storage?
500
A feature of an operating system that enables a computer to be able to compensate shortages of physical memory by transferring pages of data from random access memory to disk storage.
What is virtual memory?