Operating System
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Tuesday, October 17, 2017
Monday, October 16, 2017
Operating System Quiz
Operating System Quiz
Saturday, October 14, 2017
Operating Systems Series 3
Physical
memory is broken into fixed-sized blocks called ________.
a) frames
b) pages
c) backing store
d) None of these
a) frames
b) pages
c) backing store
d) None of these
The __________
is used as an index into the page table.
a) frame bit
b) page number
c) page offset
d) frame offset
a) frame bit
b) page number
c) page offset
d) frame offset
The _____
table contains the base address of each page in physical memory.
a) process
b) memory
c) page
d) frame
a) process
b) memory
c) page
d) frame
If the size of
logical address space is 2 to the power of m, and a page size is 2 to the power
of n addressing units, then the high order _____ bits of a logical address
designate the page number, and the ____ low order bits designate the page
offset.
a) m, n
b) n, m
c) m – n, m
d) m – n, n
a) m, n
b) n, m
c) m – n, m
d) m – n, n
For every
process there is a __________.
a) page table
b) copy of page table
c) pointer to page table
d) All of these
a) page table
b) copy of page table
c) pointer to page table
d) All of these
A process is
selected from the ______ queue by the ________ scheduler, to be executed.
a) blocked, short term
b) wait, long term
c) ready, short term
d) ready, long term
a) blocked, short term
b) wait, long term
c) ready, short term
d) ready, long term
Turnaround time is :
a) the total waiting time for a process to finish execution
b) the total time spent in the ready queue
c) the total time spent in the running queue
d) the total time from the completion till the submission of a process
a) the total waiting time for a process to finish execution
b) the total time spent in the ready queue
c) the total time spent in the running queue
d) the total time from the completion till the submission of a process
If a page number is not found in the TLB, then it is known
as a :
a) TLB miss
b) buffer miss
c) TLB hit
a) TLB miss
b) buffer miss
c) TLB hit
The percentage
of times a page number is found in the TLB is known as :
a) miss ratio
b) hit ratio
c) miss percent
d) None of these
a) miss ratio
b) hit ratio
c) miss percent
d) None of these
Memory
protection in a paged environment is accomplished by :
a) protection algorithm with each page
b) restricted access rights to users
c) restriction on page visibility
d) protection bit with each page
a) protection algorithm with each page
b) restricted access rights to users
c) restriction on page visibility
d) protection bit with each page
Illegal addresses are trapped using the _____ bit.
a) error
b) protection
c) valid – invalid
d) access
a) error
b) protection
c) valid – invalid
d) access
In a paged
memory, the page hit ratio is 0.35. The required to access a page in secondary
memory is equal to 100 ns. The time required to access a page in primary memory
is 10 ns. The average time required to access a page is :
a) 3.0 ns
b) 68.0 ns
c) 68.5 ns
d) 78.5 ns
a) 3.0 ns
b) 68.0 ns
c) 68.5 ns
d) 78.5 ns
Round robin
scheduling falls under the category of :
a) Non preemptive scheduling
b) Preemptive scheduling
c) None of these
a) Non preemptive scheduling
b) Preemptive scheduling
c) None of these
With round
robin scheduling algorithm in a time shared system,
a) using very large time slices converts it into First come First served scheduling algorithm
b) using very small time slices converts it into First come First served scheduling algorithm
c) using extremely small time slices increases performance
d) using very small time slices converts it into Shortest Job First algorithm
a) using very large time slices converts it into First come First served scheduling algorithm
b) using very small time slices converts it into First come First served scheduling algorithm
c) using extremely small time slices increases performance
d) using very small time slices converts it into Shortest Job First algorithm
Friday, October 13, 2017
Operating System Series 2
With
relocation and limit registers, each logical address must be _______ the limit
register.
a) less than
b) equal to
c) greater than
d) None of these
a) less than
b) equal to
c) greater than
d) None of these
The first fit,
best fit and worst fit are strategies to select a ______.
a) process from a queue to put in memory
b) processor to run the next process
c) free hole from a set of available holes
d) All of these
a) process from a queue to put in memory
b) processor to run the next process
c) free hole from a set of available holes
d) All of these
Which of the
following do not belong to queues for processes ?
a) Job Queue
b) PCB queue
c) Device Queue
d) Ready Queue
a) Job Queue
b) PCB queue
c) Device Queue
d) Ready Queue
When the
process issues an I/O request :
a) It is placed in an I/O queue
b) It is placed in a waiting queue
c) It is placed in the ready queue
d) It is placed in the Job queue
a) It is placed in an I/O queue
b) It is placed in a waiting queue
c) It is placed in the ready queue
d) It is placed in the Job queue
In a
time-sharing operating system, when the time slot given to a process is
completed, the process goes from the running state to the :
a) Blocked state
b) Ready state
c) Suspended state
d) Terminated state
a) Blocked state
b) Ready state
c) Suspended state
d) Terminated state
The context of a process in the PCB of a process does not
contain :
a) the value of the CPU registers
b) the process state
c) memory-management information
d) context switch time
a) the value of the CPU registers
b) the process state
c) memory-management information
d) context switch time
Which of the following state transitions is not possible ?
a) blocked to running
b) ready to running
c) blocked to ready
d) running to blocked
a) blocked to running
b) ready to running
c) blocked to ready
d) running to blocked
__________ is generally faster than _________ and
_________.
a) first fit, best fit, worst fit
b) best fit, first fit, worst fit
c) worst fit, best fit, first fit
d) None of these
a) first fit, best fit, worst fit
b) best fit, first fit, worst fit
c) worst fit, best fit, first fit
d) None of these
External
fragmentation exists when :
a) enough total memory exists to satisfy a request but it is not contiguous
b) the total memory is insufficient to satisfy a request
c) a request cannot be satisfied even when the total memory is free
d) None of these
a) enough total memory exists to satisfy a request but it is not contiguous
b) the total memory is insufficient to satisfy a request
c) a request cannot be satisfied even when the total memory is free
d) None of these
External
fragmentation will not occur when :
a) first fit is used
b) best fit is used
c) worst fit is used
d) no matter which algorithm is used, it will always occur
a) first fit is used
b) best fit is used
c) worst fit is used
d) no matter which algorithm is used, it will always occur
The interval
from the time of submission of a process to the time of completion is termed as
a) waiting time
b) turnaround time
c) response time
d) throughput
a) waiting time
b) turnaround time
c) response time
d) throughput
Which
scheduling algorithm allocates the CPU first to the process that requests the
CPU first?
a) first-come, first-served scheduling
b) shortest job scheduling
c) priority scheduling
d) none of the mentioned
a) first-come, first-served scheduling
b) shortest job scheduling
c) priority scheduling
d) none of the mentioned
In priority
scheduling algorithm
a) CPU is allocated to the process with highest priority
b) CPU is allocated to the process with lowest priority
c) equal priority processes can not be scheduled
d) none of the mentioned
a) CPU is allocated to the process with highest priority
b) CPU is allocated to the process with lowest priority
c) equal priority processes can not be scheduled
d) none of the mentioned
In priority
scheduling algorithm, when a process arrives at the ready queue, its priority
is compared with the priority of
a) all process
b) currently running process
c) parent process
d) init process
a) all process
b) currently running process
c) parent process
d) init process
Process are
classified into different groups in
a) shortest job scheduling algorithm
b) round robin scheduling algorithm
c) priority scheduling algorithm
d) multilevel queue scheduling algorithm
a) shortest job scheduling algorithm
b) round robin scheduling algorithm
c) priority scheduling algorithm
d) multilevel queue scheduling algorithm
Thursday, October 12, 2017
Operating System Series 1
The systems
which allows only one process execution at a time, are called
a) uniprogramming systems
b) uniprocessing systems
c) unitasking systems
d) none of the mentioned
a) uniprogramming systems
b) uniprocessing systems
c) unitasking systems
d) none of the mentioned
In Unix, Which system call creates the new process?
a) fork
b) create
c) new
d) none of the mentioned
a) fork
b) create
c) new
d) none of the mentioned
What is the
ready state of a process?
a) when process is scheduled to run after some execution
b) when process is unable to run until some task has been completed
c) when process is using the CPU
d) none of the mentioned
a) when process is scheduled to run after some execution
b) when process is unable to run until some task has been completed
c) when process is using the CPU
d) none of the mentioned
What is interprocess
communication?
a) communication within the process
b) communication between two process
c) communication between two threads of same process
d) none of the mentioned
a) communication within the process
b) communication between two process
c) communication between two threads of same process
d) none of the mentioned
A set of
processes is deadlock if
a) each process is blocked and will remain so forever
b) each process is terminated
c) all processes are trying to kill each other
d) none of the mentioned
a) each process is blocked and will remain so forever
b) each process is terminated
c) all processes are trying to kill each other
d) none of the mentioned
The address of
the next instruction to be executed by the current process is provided by the
a) CPU registers
b) program counter
c) process stack
d) pipe
a) CPU registers
b) program counter
c) process stack
d) pipe
Which one of
the following is the address generated by CPU?
a) physical address
b) absolute address
c) logical address
d) none of the mentioned
a) physical address
b) absolute address
c) logical address
d) none of the mentioned
Run time
mapping from virtual to physical address is done by
a) memory management unit
b) CPU
c) PCI
d) none of the mentioned
a) memory management unit
b) CPU
c) PCI
d) none of the mentioned
Memory
management technique in which system stores and retrieves data from secondary
storage for use in main memory is called
a) fragmentation
b) paging
c) mapping
d) none of the mentioned
a) fragmentation
b) paging
c) mapping
d) none of the mentioned
The address of
a page table in memory is pointed by
a) stack pointer
b) page table base register
c) page register
d) program counter
a) stack pointer
b) page table base register
c) page register
d) program counter
Operating
System maintains the page table for
a) each process
b) each thread
c) each instruction
d) each address
a) each process
b) each thread
c) each instruction
d) each address
The number of
processes completed per unit time is known as __________.
a) Output
b) Throughput
c) Efficiency
d) Capacity
a) Output
b) Throughput
c) Efficiency
d) Capacity
The Process
Control Block is :
a) Process type variable
b) Data Structure
c) a secondary storage section
d) a Block in memory
a) Process type variable
b) Data Structure
c) a secondary storage section
d) a Block in memory
The degree of
multi-programming is :
a) the number of processes executed per unit time
b) the number of processes in the ready queue
c) the number of processes in the I/O queue
d) the number of processes in memory
a) the number of processes executed per unit time
b) the number of processes in the ready queue
c) the number of processes in the I/O queue
d) the number of processes in memory
In contiguous
memory allocation :
a) each process is contained in a single contiguous section of memory
b) all processes are contained in a single contiguous section of memory
c) the memory space is contiguous
d) None of these
a) each process is contained in a single contiguous section of memory
b) all processes are contained in a single contiguous section of memory
c) the memory space is contiguous
d) None of these
Thursday, September 28, 2017
Software Engineering Series 1
1) Spiral Model was developed by?
- Bev Littlewood
- Berry Bohem
- Roger Pressman
- Victor Bisili
Answer = B
Explanation: Spiral model was developed by Berry Bohem in 1986 in his article "A Spiral Model of Software Development and Enhancement"
Explanation: Spiral model was developed by Berry Bohem in 1986 in his article "A Spiral Model of Software Development and Enhancement"
2) Which model is popular for students small projects ?
- Waterfall Model
- Spiral Model
- Quick and Fix model
- Prototyping Model
Answer = A
Explanation: No Explanation
Explanation: No Explanation
3) Which is not a software life cycle model?
- Spiral Model
- Waterfall Model
- Prototyping Model
- Capability maturity Model
Answer = D
Explanation:Capability maturity model is not a software life cycle model
Explanation:Capability maturity model is not a software life cycle model
4) Project risk factor is considered in ?
- Spiral Model
- Waterfall Model
- Prototyping Model
- Iterative enhancement Model
Answer = A
Explanation:Aim of Risk analysis phase in the spiral model is to eliminate the high risk problems before they threaten the project operation or cost.
Explanation:Aim of Risk analysis phase in the spiral model is to eliminate the high risk problems before they threaten the project operation or cost.
5) SDLC stands for ?
- Software design life cycle
- Software development life cycle
- System design life cycle
- System development life cycle
Answer = B
Explanation:Full form of SDLC is software development life cycle.
Explanation:Full form of SDLC is software development life cycle.
6) Build and Fix model has?
- 3 Phases
- 1 Phases
- 2 Phases
- 4 Phases
Answer = C
Explanation:Build and fix model has 2 phases one is " build " and other is " fix " .
Explanation:Build and fix model has 2 phases one is " build " and other is " fix " .
7) SRS stands for ?
- Software requirement specification
- Software requirement solution
- System requirement specification
- None of Above
Answer = A
Explanation: SRS acts as a contract between the developer and the user.
Explanation: SRS acts as a contract between the developer and the user.
8) Waterfall model is not suitable for ?
- Small Projects
- Complex Projects
- Accommodating change
- None of Above
Answer = C
Explanation:Waterfall model does not accommodate any change that's why this model is used in those situations where requirements are well understood.
Explanation:Waterfall model does not accommodate any change that's why this model is used in those situations where requirements are well understood.
9) RAD stands for ?
- Rapid Application Development
- Relative Application Development
- Ready Application Development
- Repeated Application Development
Answer =A
10) RAD Model was purposed by ?
- IBM
- Motorola
- Microsoft
- Lucent Technologies
Answer =A
Explanation:RAD Model was purposed by IBM in 1980s through the book of James Martin entitles "Rapid Application Development"
Explanation:RAD Model was purposed by IBM in 1980s through the book of James Martin entitles "Rapid Application Development"
Wednesday, September 27, 2017
Web Technologies Series 1...
1. Which of the following options
is correct with regard to HTML?
(a) It is a modelling language
(b) It is a DTP language
(c) It is a partial programming language
(d) It is used to structure documents
(e) It is a scripting language.
2. Consider the following statement:
GET /cgi-bin/dispenser.pl&want=whatsnew.html HTTP/1.0
Which of the following options is a correct one?
(a) The above statement is a part of a request from a web client
(b) The above statement is a part of the input to a CGI program
(c) want is a variable and whatsnew.html is a value
(d) want is a variable and whatsnew.html HTTP/1.0 is the value
(e) dispenser.pl may be a CGI program.
3. When trying to access a URL, the following message is displayed on the browser:
Server; Error 403
What could be the reason for the message?
(a) The requested HTML file is not available
(b) The URL refers to a CGI script and the header of the script does not indicate where the interpreter is located
(c) The path to the interpreter of the script file is invalid
(d) The first line of the output from the script is not a valid HTTP header
(e) The requested HTML file or CGI script has insufficient permission.
4. Which of the following statements is incorrect regarding multimedia on the web?
(a) The MPEG, AIFF and WAV are cross-platform formats
(b) The MPEG, AU and MIDI are cross-platform formats
(c) The SND format has a relatively low fidelity
(d) VRML can be used to model and display 3D interactive graphics
(e) The dynsrc attribute in the <img> element can be used to include videos in web pages.
5. What would be the colours of the RGB where the hexadecimal values are #FF0000, #00FF00 and #0000FF respectively?
(a) Blue, Green, Red
(b) Green, Blue, Red
(c) Green, Red, Blue
(d) Red, Blue, Green
(e) Red, Green, Blue.
6. The elements <DIV> and <SPAN> have the following characteristics
(a) Element <DIV> inherits properties defined for <SPAN> in a stylesheet
(b) <DIV> and <SPAN> have no real meanings as html tags unless stylesheet is applied
(c) Elements <SPAN> and <DIV> define content to be inline or block-level
(d) <DIV> and <SPAN> are used as alternatives for the element <P>
(e) <DIV> is used inside element <P>.
7. Which of the following statement is not true regarding JavaScript?
(a) JavaScript is a loosely typed language
(b) JavaScript is an object-based language
(c) JavaScript is event driven
(d) A JavaScript embedded in an HTML document is compiled and executed by the client browser
(e) JavaScript can not run in stand-alone mode (without a browser).
8. The following is a web-page:
<html>
<head> <title>JavaScript</title> </head>
<body bgcolor="#0000ff">
<script language="JavaScript">
<!-- document.write("<h1> hello world </h1>"); //-->
</script>
</body>
</html>
When the above web page is loaded into a browser, what will happen?
(a) The body of the web page will not contain any text
(b) The body of the web page will contain the text “<h1> hello world </h1>”
(c) The body of the web page will contain the text “hello world” as an H1 heading
(d) The background color of the web page will be green
(e) document.write("<h1> hello world </h1 >”); is a comment.
9. The following statements are about three important browser objects in JavaScript.
I. window object : The highest of all objects in the client-side JavaScript object hierarchy.
II. navigator object : A collection of information about the browser. Useful in browser sniffing.
III. document object : Provides access to the document being viewed.
Which of the above statements is/are true?
(a) Only (I) above
(b) Only (II) above
(c) Only (III) above
(d) Both (I) and (II) above
(e) All (I), (II) and (III) above.
10. Consider the following script:
<html>
<head><title>JavaScript</title></head>
<body>
<script language="JavaScript">
var a=80
var b=(a==80 ? "pass" :"fail");
document.write(b)
</script>
</body>
</html>
What will be the output of the above script?
(a) pass
(b) fail
(c) null
(d) 80
(e) Error at line 6.
(a) It is a modelling language
(b) It is a DTP language
(c) It is a partial programming language
(d) It is used to structure documents
(e) It is a scripting language.
2. Consider the following statement:
GET /cgi-bin/dispenser.pl&want=whatsnew.html HTTP/1.0
Which of the following options is a correct one?
(a) The above statement is a part of a request from a web client
(b) The above statement is a part of the input to a CGI program
(c) want is a variable and whatsnew.html is a value
(d) want is a variable and whatsnew.html HTTP/1.0 is the value
(e) dispenser.pl may be a CGI program.
3. When trying to access a URL, the following message is displayed on the browser:
Server; Error 403
What could be the reason for the message?
(a) The requested HTML file is not available
(b) The URL refers to a CGI script and the header of the script does not indicate where the interpreter is located
(c) The path to the interpreter of the script file is invalid
(d) The first line of the output from the script is not a valid HTTP header
(e) The requested HTML file or CGI script has insufficient permission.
4. Which of the following statements is incorrect regarding multimedia on the web?
(a) The MPEG, AIFF and WAV are cross-platform formats
(b) The MPEG, AU and MIDI are cross-platform formats
(c) The SND format has a relatively low fidelity
(d) VRML can be used to model and display 3D interactive graphics
(e) The dynsrc attribute in the <img> element can be used to include videos in web pages.
5. What would be the colours of the RGB where the hexadecimal values are #FF0000, #00FF00 and #0000FF respectively?
(a) Blue, Green, Red
(b) Green, Blue, Red
(c) Green, Red, Blue
(d) Red, Blue, Green
(e) Red, Green, Blue.
6. The elements <DIV> and <SPAN> have the following characteristics
(a) Element <DIV> inherits properties defined for <SPAN> in a stylesheet
(b) <DIV> and <SPAN> have no real meanings as html tags unless stylesheet is applied
(c) Elements <SPAN> and <DIV> define content to be inline or block-level
(d) <DIV> and <SPAN> are used as alternatives for the element <P>
(e) <DIV> is used inside element <P>.
7. Which of the following statement is not true regarding JavaScript?
(a) JavaScript is a loosely typed language
(b) JavaScript is an object-based language
(c) JavaScript is event driven
(d) A JavaScript embedded in an HTML document is compiled and executed by the client browser
(e) JavaScript can not run in stand-alone mode (without a browser).
8. The following is a web-page:
<html>
<head> <title>JavaScript</title> </head>
<body bgcolor="#0000ff">
<script language="JavaScript">
<!-- document.write("<h1> hello world </h1>"); //-->
</script>
</body>
</html>
When the above web page is loaded into a browser, what will happen?
(a) The body of the web page will not contain any text
(b) The body of the web page will contain the text “<h1> hello world </h1>”
(c) The body of the web page will contain the text “hello world” as an H1 heading
(d) The background color of the web page will be green
(e) document.write("<h1> hello world </h1 >”); is a comment.
9. The following statements are about three important browser objects in JavaScript.
I. window object : The highest of all objects in the client-side JavaScript object hierarchy.
II. navigator object : A collection of information about the browser. Useful in browser sniffing.
III. document object : Provides access to the document being viewed.
Which of the above statements is/are true?
(a) Only (I) above
(b) Only (II) above
(c) Only (III) above
(d) Both (I) and (II) above
(e) All (I), (II) and (III) above.
10. Consider the following script:
<html>
<head><title>JavaScript</title></head>
<body>
<script language="JavaScript">
var a=80
var b=(a==80 ? "pass" :"fail");
document.write(b)
</script>
</body>
</html>
What will be the output of the above script?
(a) pass
(b) fail
(c) null
(d) 80
(e) Error at line 6.
Answers
Answer Reason
1. D All the other options are wrong
and incorrect for the question asked.
2. E All the other options are wrong and
incorrect for the question asked.
3. E Server error 403 means insufficient
permission.
4. A All the other options are correct
for the question asked.
5. E The values are hexadecimal
equivalent for Red, Green, Blue.
6. C According to the specifications
of <SPAN> and <DIV> they are used to define
the
contents inline or block level.
7. D As the remaining all the options
are correct and valid for JavaScript.
8. A Because of the comment nothing
will be printed.
9. E According to the definitions of
browser objects, all the statements are true.
10. A Because the outcome of the
ternary operator.
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