Question and Solution Paper OS Exam 1
2024/2025
human logic, machine implementation, executed
01 - Intro - OS's role in CS world
- OS bridges the ____ __ and the __ ___
- Understand OS to know in depth how a program is ___ by the computer
software, intermediary/interface, manages, services
01 - Intro - What is an operating system?
- Definition of OS:
-> A ___ that acts as an ____ between the user/application and the hardware (architecture)
-> Specifically, it ___ computer hardware resources, and provides common ___ for computer programs
changed, bare, functions/models, convenient, interface, efficient, schedulers
01 - Intro - What is an operating system? (Cont)
- Definition has ___ over the years
-> Originally, OS was very ____
-> Now, more and more ___ have been added
- Goals
-> Make the system __ to use (___)
-> Use the hardware in an ____ manner: execute multiple user tasks by time-sharing (____)>
ugly, beautiful
01 - Intro -
OS's turn the ___ into the ____
interface, convenient, interface,
01 - Intro -
The ____ provides the function we need and hides the implementation details underneath
,- Makes the system ___ to use (____): The crucial role of OS as an interface between user/applications
and hardware architecture
standard library, overhead
01 - Intro - What's the main function that an OS must provide?
-> ____
OS is not merely an interface, it works like a manager/government in a company/society (___)
manage, concurrency and parallelism, manage, protect, virtual memory, interrupt
01 - Intro - Resource Management
- ___ multiple processes to run at the same time with ____
- ___ and ___ memory, I/0 devices, __, __, etc.
process, CPU, memory, system, authentication, process
01 - Intro - OS is not merely an excellent interface, but also it provides essential functions:
1) ___ management, ___ scheduler, ____ management
2) ___ calls, Interrupts & Traps
3) _____ & authorization, allocation, process communication
actual computation, data and programs, I/O devices
01 - Intro - Generic Computer System Architecture
- CPU: Processor that performs the ___ ___
- Memory: RAM stores ____ used by the CPU
- ___: USB, disks, video board, network card, printer, etc.
concurrency, one core
01 - Intro - CPU Time Sharing
- _____: executing multiple tasks simultaneously (I/O, computing, multiple programs, etc.)
-> One task (thread) is implemented by the CPU at a time, if only __ ___
, parallelism, cannot be implemented
01 - Intro - CPU Time Sharing
- ____: Executing multiple tasks on different cores/processors
-> ____ if only one core or single-threaded OS
access time, capacity, cost, locality reference, efficiency, affordability, scalability, trade-off
01 - Intro - Why Hierarchical Design?
- Because of different ___, ___, and ___, making use of the ___, the hierarchical design can achieve ___
(small mean access time), ___ (low cost), and ___ (infinite memory capacity)
- To achieve a good ___ between speed/efficiency, cost, and capacity
kernel, device driver, device controller/interrupt handler
01 - Intro - I/O Structure & Control
- ____: Core program of an OS, always resident in a PC's memory
- ___: Software that provides an interface to the I/O device
- ___: Chipset that controls the I/O device
polling, interrupts, DMA (direct memory access)
01 - Intro - How does the program know when I/O operation is ready?
1. ___: process continuously checks if I/O is ready (ex. printer) and once ready, the process handles the
I/O operation
2. ____: I/O ____ (same blank, don't retype) CPU and the interrupt handler copies data to/from memory
3) ____: A controller for this and a device driver copies data to/from memory. An interrupt is issued
when data transfer is finished
frequently, efficiently, stop, instruction, request
01 - Intro - Interrupts
- Operating systems are interrupt driven, which means it does so __ and __ (ex. ctrl-v, end task, volume,
