Category: Operating System Objective Questions

Operating System Multiple Choice Questions on “CPU Scheduling Benefits”.

1. CPU scheduling is the basis of ___________
a) multiprocessor systems
b) multiprogramming operating systems
c) larger memory sized systems
d) none of the mentioned

Answer: b
Clarification: None.

2. With multiprogramming ______ is used productively.
a) time
b) space
c) money
d) all of the mentioned

Answer: a
Clarification: None.

3. What are the two steps of a process execution?
a) I/O & OS Burst
b) CPU & I/O Burst
c) Memory & I/O Burst
d) OS & Memory Burst

Answer: b
Clarification: None.

4. An I/O bound program will typically have ____________
a) a few very short CPU bursts
b) many very short I/O bursts
c) many very short CPU bursts
d) a few very short I/O bursts

Answer: c
Clarification: None.

5. 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

Answer: c
Clarification: None.

6. In the following cases non – preemptive scheduling occurs?
a) When a process switches from the running state to the ready state
b) When a process goes from the running state to the waiting state
c) When a process switches from the waiting state to the ready state
d) All of the mentioned

Answer: b
Clarification: There is no other choice.

7. The switching of the CPU from one process or thread to another is called ____________
a) process switch
b) task switch
c) context switch
d) all of the mentioned

Answer: d
Clarification: None.

8. What is Dispatch latency?
a) the speed of dispatching a process from running to the ready state
b) the time of dispatching a process from running to ready state and keeping the CPU idle
c) the time to stop one process and start running another one
d) none of the mentioned

Answer: c
Clarification: None.

9. Scheduling is done so as to ____________
a) increase CPU utilization
b) decrease CPU utilization
c) keep the CPU more idle
d) none of the mentioned

Answer: a
Clarification: None.

10. Scheduling is done so as to ____________
a) increase the throughput
b) decrease the throughput
c) increase the duration of a specific amount of work
d) none of the mentioned

Answer: a
Clarification: None.

11. What is Turnaround time?
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

Answer: d
Clarification: None.

12. Scheduling is done so as to ____________
a) increase the turnaround time
b) decrease the turnaround time
c) keep the turnaround time same
d) there is no relation between scheduling and turnaround time

Answer: b
Clarification: None.

13. What is Waiting time?
a) the total time in the blocked and waiting queues
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

Answer: b
Clarification: None.

14. Scheduling is done so as to ____________
a) increase the waiting time
b) keep the waiting time the same
c) decrease the waiting time
d) none of the mentioned

Answer: c
Clarification: None.

15. What is Response time?
a) the total time taken from the submission time till the completion time
b) the total time taken from the submission time till the first response is produced
c) the total time taken from submission time till the response is output
d) none of the mentioned

Answer: b

Operating System Multiple Choice Questions on “Memory Management”.

1. CPU fetches the instruction from memory according to the value of ____________
a) program counter
b) status register
c) instruction register
d) program status word

Answer: a
Clarification: None.

2. A memory buffer used to accommodate a speed differential is called ____________
a) stack pointer
b) cache
c) accumulator
d) disk buffer

Answer: b
Clarification: None.

3. 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

Answer: c
Clarification: None.

4. Run time mapping from virtual to physical address is done by ____________
a) Memory management unit
b) CPU
c) PCI
d) None of the mentioned

Answer: a
Clarification: None.

5. 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

Answer: b
Clarification: None.

6. 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

Answer: b
Clarification: None.

7. Program always deals with ____________
a) logical address
b) absolute address
c) physical address
d) relative address

Answer: a
Clarification: None.

8. The page table contains ____________
a) base address of each page in physical memory
b) page offset
c) page size
d) none of the mentioned

Answer: a
Clarification: None.

9. What is compaction?
a) a technique for overcoming internal fragmentation
b) a paging technique
c) a technique for overcoming external fragmentation
d) a technique for overcoming fatal error

Answer: c
Clarification: None.

10. Operating System maintains the page table for ____________
a) each process
b) each thread
c) each instruction
d) each address

Answer: a

Operating System Questions and Answers on “Multimedia System – Compression” and will also be useful for GRE examinations.

1. The ability to move around within a media stream is known as ___________
a) buffering
b) random access
c) access
d) sequential access

Answer: b
Clarification: None.

2. What are the two types of real time streaming?
a) live & on demand streaming
b) dead & static streaming
c) static & on demand streaming
d) on demand streaming

Answer: a
Clarification: None.

3. Random access is not allowed in ___________
a) live streaming
b) dead streaming
c) static streaming
d) on demand streaming

Answer: a
Clarification: None.

4. The streaming that takes place as the event is occurring is ___________
a) live streaming
b) dead streaming
c) static streaming
d) on demand streaming

Answer: d
Clarification: None.

5. For a computer to deliver continuous media it must guarantee the specific rate and timing requirements, also known as ___________
a) deadline
b) quality of service
c) period
d) burst time

Answer: b
Clarification: None.

6. For QOS to be implemented properly ___________
a) file systems must be efficient to meet the rate requirements of continuous media
b) network protocols must support bandwidth requirements while minimizing delay and jitter
c) all of the mentioned
d) none of the mentioned

Answer: c
Clarification: None.

7. What will happen once a file is compressed?
a) it has a better quality
b) it takes up less space for storage
c) it cannot be delivered to the client more quickly
d) none of the mentioned

Answer: b
Clarification: None.

8. Compression ratio is the ratio of ___________
a) the original file size to the size of the compressed file
b) the number of pixels in a frame of the original size to those in a frame of the compressed file
c) compressed file size to the original file size
d) none of the mentioned

Answer: a
Clarification: None.

9. Lossy and lossless are classifications of ___________
a) multimedia storage systems
b) files
c) compression algorithms
d) all of the mentioned

Answer: c
Clarification: None.

10. Lossy techniques provide ___________ when compared to lossless techniques.
a) lower compression ratios
b) much higher compression ratios
c) similar compression ratios
d) none of the mentioned

Answer: b

Operating System Multiple Choice Questions on “Signal Handling”.

1. Signals that occur at the same time, are presented to the process ____________
a) one at a time, in a particular order
b) one at a time, in no particular order
c) all at a time
d) none of the mentioned

Answer: b

2. Which of the following is not TRUE?
a) Processes may send each other signals
b) Kernel may send signals internally
c) A field is updated in the signal table when the signal is sent
d) Each signal is maintained by a single bit

Answer: c
Clarification: A field is updated in the process table when the signal is sent.

3. Signals of a given type ____________
a) are queued
b) are all sent as one
c) cannot be queued
d) none of the mentioned

Answer: b
Clarification: The signal handler will be invoked only once.

4. The three ways in which a process responds to a signal are ____________
a) ignoring the signal
b) handling the signal
c) performing some default action
d) all of the mentioned

Answer: d
Clarification: None.

5. Signals are identified by ____________
a) signal identifiers
b) signal handlers
c) signal actions
d) none of the mentioned

Answer: a
Clarification: None.

6. When a process blocks the receipt of certain signals?
a) The signals are delivered
b) The signals are not delivered
c) The signals are received until they are unblocked
d) The signals are received by the process once they are delivered

Answer: a
Clarification: None.

7. The _______ maintains pending and blocked bit vectors in the context of each process.
a) CPU
b) Memory
c) Process
d) Kernel

Answer: d
Clarification: None.

8. In UNIX, the set of masked signals can be set or cleared using the ________ function.
a) sigmask
b) sigmaskproc
c) sigprocmask
d) sigproc

Answer: c
Clarification: None.

9. The usefulness of signals as a general inter process communication mechanism is limited because ____________
a) they do not work between processes
b) they are user generated
c) they cannot carry information directly
d) none of the mentioned

Answer: c
Clarification: None.

10. The usual effect of abnormal termination of a program is ____________
a) core dump file generation
b) system crash
c) program switch
d) signal destruction

Answer: a
Clarification: None.

11. In UNIX, the abort() function sends the ________ signal to the calling process, causing abnormal termination.
a) SIGTERM
b) SIGSTOP
c) SIGABORT
d) SIGABRT

Answer: d
Clarification: None.

12. In most cases, if a process is sent a signal while it is executing a system call ____________
a) the system call will continue execution and the signal will be ignored completely
b) the system call is interrupted by the signal, and the signal handler comes in
c) the signal has no effect until the system call completes
d) none of the mentioned

Answer: c
Clarification: None.

13. A process can never be sure that a signal it has sent _____________
a) has which identifier
b) has not been lost
c) has been sent
d) all of the mentioned

Answer: b
Clarification: None.

14. In UNIX, the ______________ system call is used to send a signal.
a) sig
b) send
c) kill
d) sigsend

Answer: c

Operating System Multiple Choice Questions on “Allocation Methods”.

1. The three major methods of allocating disk space that are in wide use are _____________
a) contiguous
b) linked
c) indexed
d) all of the mentioned

Answer: d
Clarification: None.

2. In contiguous allocation _____________
a) each file must occupy a set of contiguous blocks on the disk
b) each file is a linked list of disk blocks
c) all the pointers to scattered blocks are placed together in one location
d) none of the mentioned

Answer: a
Clarification: None.

3. In linked allocation _____________
a) each file must occupy a set of contiguous blocks on the disk
b) each file is a linked list of disk blocks
c) all the pointers to scattered blocks are placed together in one location
d) none of the mentioned

Answer: b
Clarification: None.

4. In indexed allocation _____________
a) each file must occupy a set of contiguous blocks on the disk
b) each file is a linked list of disk blocks
c) all the pointers to scattered blocks are placed together in one location
d) none of the mentioned

Answer: c
Clarification: None.

5. On systems where there are multiple operating system, the decision to load a particular one is done by _____________
a) boot loader
b) bootstrap
c) process control block
d) file control block

Answer: a
Clarification: None.

6. The VFS (virtual file system) activates file system specific operations to handle local requests according to their _______
a) size
b) commands
c) timings
d) file system types

Answer: d
Clarification: None.

7. What is the real disadvantage of a linear list of directory entries?
a) size of the linear list in memory
b) linear search to find a file
c) it is not reliable
d) all of the mentioned

Answer: b
Clarification: None.

8. Contiguous allocation of a file is defined by _____________
a) disk address of the first block & length
b) length & size of the block
c) size of the block
d) total size of the file

Answer: a
Clarification: None.

9. One difficulty of contiguous allocation is _____________
a) finding space for a new file
b) inefficient
c) costly
d) time taking

Answer: a
Clarification: None.

10. _______ and ________ are the most common strategies used to select a free hole from the set of available holes.
a) First fit, Best fit
b) Worst fit, First fit
c) Best fit, Worst fit
d) None of the mentioned

Answer: a
Clarification: None.

11. The first fit and best fit algorithms suffer from _____________
a) internal fragmentation
b) external fragmentation
c) starvation
d) all of the mentioned

Answer: b
Clarification: None.

12. To solve the problem of external fragmentation ________ needs to be done periodically.
a) compaction
b) check
c) formatting
d) replacing memory

Answer: a
Clarification: None.

13. If too little space is allocated to a file _____________
a) the file will not work
b) there will not be any space for the data, as the FCB takes it all
c) the file cannot be extended
d) the file cannot be opened

Answer: c

Operating System Multiple Choice Questions on “Protection concepts”.

1. Which principle states that programs, users and even the systems be given just enough privileges to perform their task?
a) principle of operating system
b) principle of least privilege
c) principle of process scheduling
d) none of the mentioned

Answer: b

2. _______ is an approach to restricting system access to authorized users.
a) Role-based access control
b) Process-based access control
c) Job-based access control
d) None of the mentioned

Answer: a

3. For system protection, a process should access _____________
a) all the resources
b) only those resources for which it has authorization
c) few resources but authorization is not required
d) all of the mentioned

Answer: b

4. The protection domain of a process contains _____________
a) object name
b) rights-set
c) both object name and rights-set
d) none of the mentioned

Answer: c

5. If the set of resources available to the process is fixed throughout the process’s lifetime then its domain is _____________
a) static
b) dynamic
c) neither static nor dynamic
d) none of the mentioned

Answer: a
Clarification: None.

6. Access matrix model for user authentication contains _____________
a) a list of objects
b) a list of domains
c) a function which returns an object’s type
d) all of the mentioned

Answer: d
Clarification: None.

7. Global table implementation of the matrix table contains _____________
a) domain
b) object
c) right-set
d) all of the mentioned

Answer: d
Clarification: None.

8. For a domain _______ is a list of objects together with the operation allowed on these objects.
a) capability list
b) access list
c) both capability and access list
d) none of the mentioned

Answer: a
Clarification: None.

9. Which one of the following is capability based protection system?
a) hydra
b) cambridge CAP system
c) both hydra and cambridge CAP system
d) none of the mentioned

Answer: c
Clarification: None.

10. In UNIX, domain switch is accomplished via _____________
a) file system
b) user
c) superuser
d) none of the mentioned

Answer: a