1
Q
- A computer system consists of software (programs) and hardware (the physical machine and its electronic components).
- The chief piece of software, the portion of the computing system that manages all of the hardware and all of the other software
- It controls every file, every device, every section of main memory, and every nanosecond of processing time. It controls who can use the system and how. In short, it’s the boss
A
Operating system
2
Q
Four essential managers of every operating system:
A
Memory manager
Processor manager
Device manager
File manager
3
Q
At the top of the pyramid, from which users issue commands to the operating system
A
User interface
4
Q
A _________ was not always an integral part of operating systems; early systems were self-contained with all network capability added on top of existing operating systems.
A
network
5
Q
Each of the subsystem managers must perform the following tasks:
A
- Monitor its resources continuously
- Enforce the policies that determine who gets what, when, and how much
- Allocate the resource when appropriate
- Deallocate the resource when appropriate
6
Q
- In charge of main memory, also known as RAM
- Checks the validity of each request for memory space and, if it is a legal request, it allocates a portion of memory that isn’t already in use
A
Memory manager
7
Q
primary responsibility of the memory manager
A
To protect the space in main memory occupied by the operating system itself—it can’t allow any part of it to be accidentally or intentionally altered.
8
Q
function of a memory manager
A
- In charge of main memory, also known as RAM
- Checks the validity of each request for memory space and, if it is a legal request, it allocates a portion of memory that isn’t already in use
9
Q
- decides how to allocate the central processing unit (CPU)
- an important function of this is to keep track of the status of each process
A
processor manager
10
Q
instance of execution of a program
A
process
11
Q
processor manager’s two levels of responsibility:
A
- handle jobs as they enter the system
- handled by the job scheduler, the high-level portion of the processor manager, which accepts or rejects the incoming jobs - manage each process within those jobs
- handled by the process scheduler, the low-level portion of the processor manager, which is responsible for deciding which process gets the CPU and for how long
12
Q
- monitors every device, channel, and control unit
- its job is to choose the most effiecient way to alocate al of the system’s devices, printers, ports, disk drivers, and so forth, based on a scheduling policy chosen by the system’s designers
A
device manager
13
Q
function of processor manager
A
- decides how to allocate the central processing unit (CPU)
- an important function of this is to keep track of the status of each process
14
Q
function of device manager
A
- monitors every device, channel, and control unit
- its job is to choose the most effiecient way to alocate al of the system’s devices, printers, ports, disk drivers, and so forth, based on a scheduling policy chosen by the system’s designers
15
Q
- keeps track of every file in the system, including data files, program files, compilers, and applications. By using predetermined access policies, it enforces restrictions on who has access to which files
- also controls what users are allowed to do with files once they access them.
- allocates the necessary resources and later
deallocates them.
A
file manager
16
Q
function of file manager
A
- keeps track of every file in the system, including data files, program files, compilers, and applications. By using predetermined access policies, it enforces restrictions on who has access to which files
- also controls what users are allowed to do with files once they access them.
- allocates the necessary resources and later
deallocates them.
17
Q
Operating systems with Internet or networking capability have a fifth essential manager called the ________
A
Network Manager
18
Q
- provides a convenient way for users to share resources while controlling user’ access to them
A
network manager
19
Q
purpose of network manager
A
- provides a convenient way for users to share resources while controlling user’ access to them
20
Q
the portion of the operating system that users interact with directly
A
user interface
21
Q
purpose of user interface
A
the portion of the operating system that users interact with directly
22
Q
this is where the data and instructions must reside to be processed
A
main memory (RAM)
23
Q
include every peripheral unit in the system such as printers, disk drives, CD/DVD drives, flash memory, keyboards, and so on.
A
I/O devices
24
Q
- the brains with the circuitry (sometimes called the chip) to control the interpretation and execution of instructions
- it controls the operation of the entire computer system
A
CPU
25
classifications of computers by capacity and price
- mainframe
- minicomputer
- supercomputer
- microcomputer
- workstations
- servers
26
a _______ was a large machine, in size and in internal memory capacity
mainframe
27
classic example of an early mainframe
IBM 360
28
it was developed to meet the needs of smaller institutions, those with only a few dozen users
minicomputer
29
was developed primarily for government applications needing massive and fast number-crunching ability to carry out military operations and weather forecasting.
supercomputer
30
- are used for a wide range of tasks from scientific research to customer support and product development
- often used to perform the intricate calculations required to create animated motion pictures. And they help oil companies in their search for oil by analyzing massive amounts of data
supercomputer
31
was developed to offer inexpensive computation capability to individual users in the late 1970s
microcomputer
32
The distinguishing characteristic of the first microcomputer was its ____________
single-user status
33
Powerful microcomputers developed for use by commercial, educational, and govern
ment enterprises are called _____________.
workstations
34
are powerful computers that provide specialized services to other computers on client/server networks
servers
35
examples of servers
print servers, Internet servers, e-mail servers, etc.
36
distinguishing characters of early machines
physical size, cost, and memory capacity
37
At one time, computers were classified by memory capacity; now they’re distinguished by _________.
processor capacity
38
He predicted that the trend would cause computing power to rise exponentially over relatively brief periods of time. Now known as Moore’s Law
Gordon Moore
39
types of operating systems
- batch systems
- interactive systems
- real-time systems
- hybrid systems
- embedded systems
40
Jobs were entered by assembling the cards into a deck and running the entire deck of cards through a card reader as a group—a batch.
batch systems
41
The efficiency of a batch system is measured in ______________
throughput
42
the number of jobs completed in a given amount of time
throughput
43
give a faster turnaround than batch systems but are slower than the real-time systems
interactive systems
44
They were introduced to satisfy the demands of users who needed fast turnaround when debugging their programs.
interactive systems
45
are used in time-critical environments where reliability is key and data must be processed within a strict time limit.
real-time systems
46
real-time systems are used for:
- space flights
- airport traffic control
- fly-by-wire aircraft
- critical industrial processes
- certain medical equipment
- telephone switching
47
two types of real-time systems
- Hard real-time systems risk total system failure if the predicted time deadline is
missed.
- Soft real-time systems suffer performance degradation, but not total system failure,
as a consequence of a missed deadline.
48
combination of batch and interactive systems
hybrid systems
49
- They appear to be interactive because individual users can access the system and get fast responses, but such a system actually accepts and runs batch programs in the background when the interactive load is light.
- A hybrid system takes advantage of the free time between high-demand usage of the system and low-demand times. Many large computer systems are hybrids
hybrid systems
50
are computers placed inside other products to add features and capabilities.
embedded systems
51
The first generation of computers (1940–1955) was a time of vacuum tube technology and computers the size of classrooms.
1940s
52
First computer bug
a moth that had become trapped in the computer’s relays causing the system to
crash.
53
who coined the term bug for errors
Dr. Grace Hopper
54
Second-generation computers (1955–1965) were developed to meet the needs of new markets—government and business researchers.
1950s
55
Two improvements were widely adopted in secondgeneration computers
Computer operators were hired to facilitate each machine’s operation, and job scheduling was instituted. Job scheduling is a productivity improvement scheme that groups together programs with similar requirements.
56
Third-generation computers.
They were designed with faster CPUs, but their speed still caused problems when they interacted with printers and other I/O devices that ran at slower speeds
1960s
57
Solution to th sped probleems of third--generation computers
multiprogramming, which introduced the concept of loading many programs at one time and sharing the attention of a single CPU
58
what generation did program scheduling start
second-generation
59
computers had faster CPUs, creating an even greater disparity between their rapid processing speed and slower I/O access time.
1970s
60
The first Cray supercomputer was released in
1976
61
a solution to the physical limitation of thee capacity of main memory in 1970s
the development of virtual memory, which took advantage of the fact that the CPU could process only one instruction at a time
62
what doees virtual memory do
With virtual memory, the entire program didn’t need to reside in memory before execution could begin.
A system with virtual memory would divide the programs into parts and keep them in secondary storage, bringing each part into memory only as it was needed.
63
Development in the _____ dramatically improved the cost/performance ratio of computer components. Hardware was more flexible, with logical functions built on easily replaceable circuit boards
1980s
64
a word used to indicate that a program is permanently held in read-only memory (ROM), as opposed to being held in secondary storage
firmware
65
having more than one processor
multiprocessing
66
year wheree world wide web arose
1990s
67
the creation of partitions on a single server, with each partition supporting a different operating system
virtualization
68
multiple actions that can be executed at the same time.
threads
69
A process has two characteristics
* It requires space in main memory where it resides during its execution; although, from time to time, it requires other resources such as data files or I/O devices.
* It passes through several states (such as running, waiting, ready) from its initial arrival into the computer system to its completion.
70
allows applications to manage a separate process with several threads of control.
Multithreading
71
the part of the operating system that resides in memory at all times, performs the most essential operating system tasks, and is protected by hardware from user tampering.
kernel
72
a type of system developed for the earliest computers that used punched cards or tape for input, which were entered in a batch.
batch system
73
the component with the circuitry, the “chips,” to control the interpretation and execution of instructions
CPU
74
the section of the operating system responsible for controlling the use of devices. It monitors every device, channel, and control unit and chooses the most efficient way to allocate all of the system’s devices.
device manager
75
a dedicated computer system, often small and fast, that resides in a larger physical system such as jet aircraft or ships.
embedded system
76
the section of the operating system responsible for controlling the use of files
File Manager
77
software instructions or data that are stored in a fixed or “firm” way, usually implemented on read-only memory (ROM).
firmware
78
the physical machine and its components, including main memory, I/O devices, I/O channels, direct access storage devices, and the central processing unit.
hardware
79
a computer system that supports both batch and interactive processes.
hybrid system
80
a system that allows each user to interact directly with the operating system via commands entered from a keyboard
interactive system
81
the primary part of the operating system that remains in random access memory (RAM) and is charged with performing the system’s most essential tasks, such as managing main memory and disk access
kernel
82
the memory unit that works directly with the CPU and in which the data and instructions must reside in order to be processed. Also called primary storage or internal memory.
main memory
83
the historical name given to a large computer system characterized by its large size, high cost, and high performance.
mainframe
84
the section of the operating system responsible for controlling the use of memory. It checks the validity of each request for memory space and, if it’s a legal request, allocates the amount needed to execute the job
memory manager
85
a small computer equipped with all the hardware and software necessary to perform one or more tasks
microcomputer
86
a small to medium-sized computer system, also called a midrange computer
minicomputer
87
when two or more CPUs share the same main memory, most I/O devices, and the same control program routines. They service the same job stream and execute distinct processing programs concurrently
multiprocessing
88
a technique that allows a single processor to process several programs residing simultaneously in main memory and interleaving their execution by overlapping I/O requests with CPU requests.
multiprogramming
89
the section of the operating system responsible for controlling access to and the use of networked resources
network manager
89
a system of interconnected computer systems and peripheral devices that exchange information with one another.
network
90
a programming philosophy whereby programs consist of self contained, reusable modules called objects, each of which supports a specific function, but which are categorized into classes of objects that share the same function
object-oriented
91
the software that manages all the resources of a computer system.
operating system
92
a composite of two submanagers, the Job Scheduler and the Process Scheduler, which decides how to allocate the CPU.
Processor Manager
93
a computing system used in time-critical environments that require guaranteed response times, such as navigation systems, rapid transit systems, and industrial control systems.
real-time system
94
a node that provides to clients various network services, such as file retrieval, printing, or database access services.
server
95
the fastest, most sophisticated computers made, used for complex calculations
supercomputer
96
a collection of programs used to perform certain tasks. Software falls into three main categories: operating system programs, compilers and assemblers, and application programs.
software
97
a place where data is stored in the computer system. Primary storage is main memory and secondary storage is nonvolatile media.
storage
98
a portion of a program that can run independently of other portions. Multithreaded application programs can have several threads running at one time with
the same or different priorities
thread
99
a composite measure of a system’s efficiency that counts the number of jobs served in a given unit of time.
throughput
100
the creation of a virtual version of hardware or software. Operating system virtualization allows a single CPU to run multiple operating system images at the same time.
virtualization
101
a desktop computer attached to a local area network that serves as an access point to that network
workstation
102
OS
flashcards
Decks in class (18)
# Cards
-
Chapter 1103
-
Chapter 25
-
Review Questions13
-
Chapter 361
-
Chapter 441
-
Key Terms79
-
Chapter 527
-
Chapter 5 key terms19
-
Chapter 3 Key Terms32
-
Chapter 4 Key Terms37
-
Chapter 2 Key Terms18
-
Chapter 1 Key Terms32
-
Chapter 645
-
Chapter 6 Key Terms25
-
Chapter 756
-
Chapter 7 Key Terms42
-
Chapter 8 Key Terms33
-
Chapter 847
