Quiz Sail Part 2 Flashcards
Access matrix model for user authentication contains:
A: a list of objects
B: a function which returns an object’s type
C: a list of domains
D: all of the mentioned
D: all of the mentioned
In the single level directory:
A: all of the mentioned
B: all files must have unique names
C: all files must have unique owners
D: all directories must have unique names
B: all files must have unique names
A parent process calling –?– system call will be suspended until children processes terminate.
A: fork
B: exit
C: wait
D: exec
C: wait
In a system that does not support swapping:
A: binding of symbolic addresses to physical addresses normally takes place during execution
B: the compiler normally binds symbolic addresses (variables) to relocatable addresses
C: the loader binds relocatable addresses to physical addresses
D: the compiler normally binds symbolic addresses to physical addresses
B: the compiler normally binds symbolic addresses (variables) to relocatable addresses
What is breach of availability?
A: This violation involves unauthorized use of resources
B: This violation involves unauthorized destruction of data
C: This violation involves unauthorized modification of data
D: This type of violation involves unauthorized reading of data
B: This violation involves unauthorized destruction of data
To differentiate the many network services a system supports –?– are used.
A: Variables
B: Service names
C: Sockets
D: Ports
D: Ports
Spinlocks are:
A: Locks that avoid time wastage in context switches
B: CPU cycles wasting locks over critical sections of programs
C: Locks that work better on multiprocessor systems
D: All of the mentioned
D: All of the mentioned
The code segment that misuses its environment is called a:
A: code stacker
B: trojan horse
C: internal thief
D: none of the mentioned
B: trojan horse
The circular wait condition can be prevented by:
A: using thread
B: defining a linear ordering of resource types
C: all of the mentioned
D: using pipes
B: defining a linear ordering of resource types
The idea of overlays is to:
A: all of the mentioned
B: data that are needed at any given time
C: enable a process to be larger than the amount of memory allocated to it
D: keep in memory only those instructions
A: all of the mentioned
External fragmentation exists when:
A: a request cannot be satisfied even when the total memory is free
B: none of the mentioned
C: the total memory is insufficient to satisfy a request
D: enough total memory exists to satisfy a request but it is not contiguous
D: enough total memory exists to satisfy a request but it is not contiguous
The usefulness of signals as a general inter process communication mechanism is limited because:
A: none of the mentioned
B: they cannot carry information directly
C: they do not work between processes
D: they are user generated
B: they cannot carry information directly
Error handler codes, to handle unusual errors are:
A: almost never executed
B: executed very often
C: none of the mentioned
D: executed periodically
A: almost never executed
A file is a/an –?– data type.
A: abstract
B: private
C: primitive
A: abstract
The current directory contains, most of the files that are:
A: of current interest to the user
B: not of current interest to the system
C: not used in the system
D: stored currently in the system
A: of current interest to the user
The –?– keeps state information about the use of I/O components.
A: OS
B: CPU
C: shell
D: kernel
D: kernel
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: Terminated state
C: Suspended state
D: Ready state
D: Ready state
When an attempt is to make a machine or network resource unavailable to its intended users, the attack is called:
A: tarvation attack
B: slow read attack
C: denial-of-service attack
D: spoofed attack
C: denial-of-service attack
In operating system, each process has its own:
A: open files
B: address space and global variables
C: all of the mentioned
D: pending alarms, signals and signal handlers
C: all of the mentioned
In UNIX, even an ’empty’ disk has a percentage of its space lost to:
A: stacks
B: programs
C: inodes
D: virtual memory
C: inodes
Swap space exists in:
A: primary memory
B: secondary memory
C: cpu
D: none of the mentioned
B: secondary memory
_____ is the concept in which a process is copied into main memory from the secondary memory according to the requirement.
A: Swapping
B: Paging
C: Segmentation
D: Demand paging
D: Demand paging
The minimum number of frames to be allocated to a process is decided by the:
A: the amount of available physical memory
B: none of the mentioned
C: operating System
D: instruction set architecture
D: instruction set architecture
What is all-or-nothing situation for sharing in memory?
A: Program makes all its data available to be accessed
B: It prohibits access to some
C: It separates program memory and data memory
D: It creates rules who can access program memory
A: Program makes all its data available to be accessed
Those processes should be aborted on occurrence of a deadlock, the termination of which:
A: safety is not hampered
B: all of the mentioned
C: is more time consuming
D: incurs minimum cost
D: incurs minimum cost
Which two rights allow a process to change the entries in a column?
A: owner and transfer
B: deny and copy
C: copy and transfer
D: copy and owner
C: copy and transfer
RPC provides a(an) –?– on the client side, a separate one for each remote procedure.
A: identifier
B: name
C: process identifier
D: stub
D: stub
If the swap space is simply a large file, within the file system, –?– used to create it, name it and allocate its space.
A: swap space storage manager is
B: normal file system routines cannot be
C: special routines must be
D: normal file system routines can be
D: normal file system routines can be
When the valid – invalid bit is set to valid, it means that the associated page:
A: is the system’s physical address space
B: is in the process’s logical address space
C: is in the TLB
D: has data in it
B: is in the process’s logical address space
Multipartite viruses attack on:
A: files
B: memory
C: all of the mentioned
D: boot sector
C: all of the mentioned
Cancellation point is the point where:
A: the thread can be cancelled – safely or otherwise doesn’t matter
B: the thread can be cancelled safely
C: the whole process can be cancelled safely
D: none of the mentioned
B: the thread can be cancelled safely
In paging the user provides only –?– which is partitioned by the hardware into –?– and –?–
A: one offset, page number, address
B: page number, offset, address
C: none of the mentioned
D: one address, page number, offset
D: one address, page number, offset
The priority of a real time task:
A: none of the mentioned
B: must degrade over time
C: must not degrade over time
D: may degrade over time
C: must not degrade over time
What are various roles of protection?
A: It is used to optimize system downtime
B: It is used to detect errors which can prevent contamination of system
C: None of the mentioned
D: It is used used to accelerate a process
B: It is used to detect errors which can prevent contamination of system
A set of processes is deadlock if:
A: all processes are trying to kill each other
B: each process is blocked and will remain so forever
C: none of the mentioned
D: each process is terminated
B: each process is blocked and will remain so forever
In the Many to One model, if a thread makes a blocking system call:
A: none of the mentioned
B: the entire process will run
C: a part of the process will stay blocked, with the rest running
D: the entire process will be blocked
D: the entire process will be blocked
The two methods how LRU page replacement policy can be implemented in hardware are:
A: RAM & Registers
B: Stack & Counters
C: Registers & RAM
D: Counters & Registers
B: Stack & Counters
When is the Many to One model at an advantage?
A: When there is a single processor
B: None of the mentioned
C: When the program has to be multi-threaded
D: When the program does not need multithreading
D: When the program does not need multithreading
A process can be:
A: single threaded
B: both single threaded and multithreaded
C: none of the mentioned
D: multithreaded
B: both single threaded and multithreaded
An I/O bound program will typically have:
A: many very short I/O bursts
B: many very short CPU bursts
C: a few very short CPU bursts
D: a few very short I/O bursts
B: many very short CPU bursts
An absolute path name begins at the:
A: stem
B: root
C: current directory
D: leaf
B: root
On most computer systems, the internal components are designed around a common:
A: word size
B: byte size
C: protocol
D: interface
A: word size
Real time systems must have:
A: non preemptive kernels
B: neither preemptive nor non preemptive kernels
C: preemptive kernels or non preemptive kernels
D: preemptive kernels
D: preemptive kernels
A program is generally composed of several different localities, which –?– overlap.
A: do not
B: must
C: must not
D: may
D: may
A page fault occurs when:
A: a page is invisible
B: a page cannot be accessed due to its absence from memory
C: a page gives inconsistent data
D: all of the mentioned
B: a page cannot be accessed due to its absence from memory
A multilevel page table is preferred in comparison to a single level page table for translating virtual address to physical address because:
A: it helps to reduce the size of page table needed to implement the virtual address space of a process
B: it reduces the memory access time to read or write a memory location
C: it is required by the translation lookaside buffer
D: it helps to reduce the number of page faults in page replacement algorithms
A: it helps to reduce the size of page table needed to implement the virtual address space of a process
A thread is also called:
A: Heavy Weight Process(HWP)
B: Process
C: None of the mentioned
D: Light Weight Process(LWP)
D: Light Weight Process(LWP)
With relocation and limit registers, each logical address must be –?– the limit register.
A: greater than
B: less than
C: equal to
D: none of the mentioned
B: less than
The interrupt vector contains:
A: the interrupts
B: the identifiers of interrupts
C: the memory addresses of specialized interrupt handlers
D: the device addresses
C: the memory addresses of specialized interrupt handlers
Consider a machine in which all memory reference instructions have only one memory address, for them we need at least –?– frame(s).
A: one
B: none of the mentioned
C: two
D: three
C: two
The way/s in which a process responds to a signal are:
A: performing some default action
B: handling the signal
C: ignoring the signal
D: all of the mentioned
D: all of the mentioned
The growing phase is a phase in which:
A: A transaction may release locks, and does obtain new locks
B: A transaction may obtain locks, and releases a few or all of them
C: A transaction may release locks, but does not obtain any new locks
D: A transaction may obtain locks, but does not release any
D: A transaction may obtain locks, but does not release any
For a domain _______ is a list of objects together with the operation allowed on these objects.
A: access list
B: both capability and access list
C: none of the mentioned
D: capability list
D: capability list
A non blocking system call:
A: halts the execution of the application for an extended time
B: none of the mentioned
C: does not block the interrupts
D: does not halt the execution of the application
D: does not halt the execution of the application
Scheduling is done so as to:
Increase Throughput
What is best solution to have effect of unbounded number if base/bound registers?
A: Tagged architecture
B: Segmentation
C: Fence method
D: None of the mentioned
B: Segmentation
The file name is generally split into two parts:
A: extension & name
B: name & identifier
C: type & extension
D: identifier & type
A: extension & name
If multiple threads are concurrently searching through a database and one thread returns the result then the remaining threads must be:
A: protected
B: cancelled
C: continued
D: none of the mentioned
B: cancelled
The page table registers should be built with:
A: very low speed logic
B: none of the mentioned
C: very high speed logic
D: a large memory space
C: very high speed logic
An interrupt vector:
A: is a unique identity given to an interrupt
B: none of the mentioned
C: is a unique device number that is indexed by an address
D: is an address that is indexed to an interrupt handler
D: is an address that is indexed to an interrupt handler
The FAT is used much as a:
A: stack
B: linked list
C: data
D: pointer
B: linked list
Event latency is:
A: the amount of time from event occurrence till the event crashes
B: the amount of time an event takes to occur from when the system started
C: the amount of time from the event occurrence till the system stops
D: the amount of time that elapses from when an event occurs to when it is serviced.
D: the amount of time that elapses from when an event occurs to when it is serviced.
Messages sent by a process:
A: have to be a variable size
B: None of the mentioned
C: can be fixed or variable sized
D: have to be of a fixed size
C: can be fixed or variable sized
If a process is executing in its critical section, then no other processes can be executing in their critical section. This condition is called:
A: critical exclusion
B: mutual exclusion
C: asynchronous exclusion
D: synchronous exclusion
B: mutual exclusion
With a shared file:
A: the changes made by one person are not reflected to the other
B: there are two copies of the file
C: actual file exists
D: the changes made by one person are reflected to the other
D: the changes made by one person are reflected to the other
If a thread invokes the exec system call:
A: none of the mentioned
B: the exec is ignored as it is invoked by a thread.
C: only the exec executes as a separate process.
D: the program specified in the parameter to exec will replace the entire process
D: the program specified in the parameter to exec will replace the entire process
Every time a request for allocation cannot be granted immediately, the detection algorithm is invoked. This will help identify:
A: the set of processes in the deadlock queue
B: the set of processes that have been deadlocked
C: the specific process that caused the deadlock
D: all of the mentioned
B: the set of processes that have been deadlocked
Which of the following does not interrupt a running process?
A: Scheduler process
B: A device
C: Timer
D: Power failure
A: Scheduler process
The header and trailer of a sector contain information used by the disk controller such as –?– and –?–
A: main section & disk identifier
B: sector number & main section
C: error correcting codes (ECC) & sector number
D: disk identifier & sector number
C: error correcting codes (ECC) & sector number
Once the changes are written to the log, they are considered to be:
A: completed
B: committed
C: none of the mentioned
D: aborted
B: committed
The idea behind thread pools is:
A: none of the mentioned
B: all threads in a pool distribute the task equally among themselves
C: a number of threads are created at process startup and placed in a pool where they sit and wait for work
D: when a process begins, a pool of threads is chosen from the many existing and each thread is allotted equal amount of work
C: a number of threads are created at process startup and placed in a pool where they sit and wait for work
A process is thrashing if:
A: it spends a lot of time executing, rather than paging
B: it has no memory allocated to it
C: none of the mentioned
D: it spends a lot of time paging, than executing
D: it spends a lot of time paging, than executing
A floppy disk is designed to rotate –?– as compared to a hard disk drive.
A: none of the mentioned
B: faster
C: at the same speed
D: slower
D: slower
Bounded capacity and Unbounded capacity queues are referred to as:
A: User defined buffering
B: Programmed buffering
C: No buffering
D: Automatic buffering
D: Automatic buffering
An IPC facility provides at least two operations:
A: delete & receive message
B: receive & send message
C: write & delete message
D: send & delete message
B: receive & send message
A semaphore is a shared integer variable:
A: that can not be more than one
B: that can not drop below zero
C: that can not be more than zero
D: that can not drop below one
B: that can not drop below zero
When a process closes the file:
A: none of the mentioned
B: all of the mentioned
C: per-process table entry is not removed
D: system wide entry’s open count is decremented
D: system wide entry’s open count is decremented
The –?– program initializes all aspects of the system, from CPU registers to device controllers and the contents of main memory, and then starts the operating system.
A: rom
B: main
C: bootstrap
D: bootloader
C: bootstrap
How is disadvantage of all-or-nothing approach overcome?
A: Fence method
B: Tagged architecture
C: Base/Bound
D: Relocation technique
B: Tagged architecture
When a process blocks the receipt of certain signals:
A: The signals are received until they are unblocked
B: The signals are delivered
C: The signals are received by the process once they are delivered
D: The signals are not delivered
B: The signals are delivered
Segment replacement algorithms are more complex than page replacement algorithms because:
A: Pages are better than segments
B: Segments have fixed sizes
C: Segments are better than pages
D: Segments have variable sizes
D: Segments have variable sizes
–?– replacement generally results in greater system throughput.
A: Universal
B: Public
C: Local
D: Global
D: Global
The –?– maintains pending and blocked bit vectors in context of each process.
A: CPU
B: Memory
C: Process
D: Kernel
D: Kernel
–?– controller sends the command placed into it, via messages to the –?– controller.
A: host, host
B: disk, disk
C: host, disk
D: disk, host
C: host, disk
If too little space is allocated to a file:
A: the file cannot be extended
B: the file cannot be opened
C: there will not be any space for the data, as the FCB takes it all
D: the file will not work
A: the file cannot be extended
When a client has a cascading mount, –?– server(s) is/are involved in a path name traversal.
A: more than two
B: at least one
C: more than three
D: more than one
D: more than one
A thread shares its resources(like data section, code section, open files, signals) with:
A: other threads that belong to the same process
B: other threads that belong to similar processes
C: all of the mentioned
D: other process similar to the one that the thread belongs to
A: other threads that belong to the same process
If the offset is legal:
A: it is added to the segment base to produce the physical memory address
B: it is used as a physical memory address itself
C: it is subtracted from the segment base to produce the physical memory address
D: none of the mentioned
B: it is used as a physical memory address itself
Thread cancellation is:
A: the task of terminating a thread before it has completed
B: none of the mentioned
C: the task of removing a thread once its work is done
D: the task of destroying the thread once its work is done
A: the task of terminating a thread before it has completed
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
C: both object name and rights-set
Virtual memory allows:
A: a program to be larger than the secondary storage
B: execution of a process without being in physical memory
C: execution of a process that may not be completely in memory
D: a program to be smaller than the physical memory
C: execution of a process that may not be completely in memory
Cost factors of process termination include:
A: All of the mentioned
B: Number of resources the deadlock process is not holding
C: CPU utilization at the time of deadlock
D: Amount of time a deadlocked process has thus far consumed during its execution
D: Amount of time a deadlocked process has thus far consumed during its execution
In fixed size partition, the degree of multiprogramming is bounded by:
A: the number of partitions
B: all of the mentioned
C: the CPU utilization
D: the memory size
A: the number of partitions
In which type of allocation method each file occupy a set of contiguous block on the disk?
A: dynamic-storage allocation
B: linked allocation
C: indexed allocation
D: contiguous allocation
D: contiguous allocation
In a safety critical system, incorrect operation:
A: does not affect much
B: causes minor problems
C: none of the mentioned
D: causes major and serious problems
D: causes major and serious problems
The base register is also known as the:
A: regular register
B: relocation register
C: basic register
D: delocation register
B: relocation register
If the set of resources available to the process is fixed throughout the process’s lifetime then its domain is:
A: dynamic
B: neither static nor dynamic
C: static
D: none of the mentioned
C: static
In the Many to Many model when a thread performs a blocking system call:
A: other threads are strictly prohibited from running
B: other threads are allowed to run
C: none of the mentioned
D: other threads only from other processes are allowed to run
B: other threads are allowed to run
Which of the following algorithms tends to minimize the process flow time?
A: First come First served
B: Earliest Deadline First
C: Shortest Job First
D: Longest Job First
C: Shortest Job First
If working set window is too small:
A: none of the mentioned
B: it will not encompass entire locality
C: it may overlap several localities
D: it will cause memory problems
B: it will not encompass entire locality
If the extents are too large, then the problem that comes in is:
A: internal fragmentation
B: all of the mentioned
C: external fragmentation
D: starvation
A: internal fragmentation
Bounded waiting implies that there exists a bound on the number of times a process is allowed to enter its critical section:
A: none of the mentioned
B: before a process has made a request to enter its critical section
C: when another process is in its critical section
D: after a process has made a request to enter its critical section and before the request is granted
D: after a process has made a request to enter its critical section and before the request is granted
Concurrent access to shared data may result in:
A: data inconsistency
B: data consistency
C: none of the mentioned
D: data insecurity
A: data inconsistency
The wait operation of the semaphore basically works on the basic –?– system call.
A: wait()
B: hold()
C: block()
D: stop()
C: block()
–?– tend to represent a major bottleneck in system performance.
A: Disks
B: CPUs
C: Programs
D: I/O
A: Disks
When an entire committed transaction is completed:
A: it is stored in the memory
B: it is removed from the log file
C: it is redone
D: none of the mentioned
B: it is removed from the log file
Every address generated by the CPU is divided into two parts:
A: frame offset & page offset
B: frame bit & page number
C: page offset & frame bit
D: page number & page offset
D: page number & page offset
The percentage of times a page number is found in the TLB is known as:
A: None of the mentioned
B: miss percent
C: miss ratio
D: hit ratio
D: hit ratio
The time required to create a new thread in an existing process is:
A: equal to the time required to create a new process
B: greater than the time required to create a new process
C: none of the mentioned
D: less than the time required to create a new process
D: less than the time required to create a new process
In the single level directory:
A: All files are contained in different directories all at the same level
B: Depends on the operating system
C: All files are contained in the same directory
D: None of the mentioned
C: All files are contained in the same directory
DMA is used for:
A: Utilizing CPU cycles
B: Low speed devices
C: All of the mentioned
D: High speed devices(disks and communications network)
D: High speed devices(disks and communications network)
When device A has a cable that plugs into device B, and device B has a cable that plugs into device C and device C plugs into a port on the computer, this arrangement is called a _________
A: cable
B: bus
C: port
D: daisy chain
D: daisy chain
An –?– uniquely identifies processes and is used to provide address space protection for that process.
A: address space identifier
B: None of the mentioned
C: address process identifier
D: address space locator
A: address space identifier
When the entries in the segment tables of two different processes point to the same physical location:
A: the segments are invalid
B: all of the mentioned
C: segments are shared
D: the processes get blocked
C: segments are shared
From the following, which is not a common file permission?
A: Read
B: Stop
C: Execute
D: Write
B: Stop
–?– writes occur in the order in which the disk subsystem receives them, and the writes are not buffered.
A: Synchronous
B: Regular
C: Irregular
D: Asynchronous
A: Synchronous
Most time-sharing systems rely on –?– to manage memory space.
A: interrupts
B: roll-in/roll-out
C: polling
D: time-slicing
D: time-slicing
A –?– is a collection of electronics that can operate a port, a bus, or a device.
A: driver
B: controller
C: host
D: bus
B: controller
Deadlock prevention is a set of methods:
A: to ensure that at least one of the necessary conditions cannot hold
B: to ensure that all of the necessary conditions do not hold
C: to recover from a deadlock
D: to decide if the requested resources for a process have to be given or not
A: to ensure that at least one of the necessary conditions cannot hold
Thread pools are useful when:
A: when we need to limit the number of threads running in the application at the same time
B: when we need to limit the number of threads running in the application as a whole
C: none of the mentioned
D: when we need to arrange the ordering of threads
A: when we need to limit the number of threads running in the application at the same time
The pattern that can be used to identify a virus is known as:
A: multipartite
B: armoured
C: virus signature
D: stealth
C: virus signature
Which of the following scheduling algorithms gives minimum average waiting time?
A: SJF
B: FCFS
C: Priority
D: Round – robin
A: SJF
Which of the following is TRUE?
A: Overlays are used to increase the size of physical memory
B: Overlays are used whenever the physical address space is smaller than the logical address space
C: Overlays are used to increase the logical address space
D: When overlays are used, the size of a process is not limited to the size of the physical memory
D: When overlays are used, the size of a process is not limited to the size of the physical memory
The interval from the time of submission of a process to the time of completion is termed as:
A: response time
B: turnaround time
C: throughput
D: waiting time
B: turnaround time
Under –?–, programs are divided into variable length pieces.
A: dynamic memory management
B: fixed partitions
C: paging
D: segmentation
D: segmentation
Mapping of file is managed by:
A: page table
B: file system
C: file metadata
D: virtual memory
C: file metadata
Interrupt latency refers to the period of time:
A: from arrival of an interrupt to the start of the interrupt service routine
B: none of the mentioned
C: from the occurrence of an event to the arrival of an interrupt
D: from the occurrence of an event to the servicing of an interrupt
A: from arrival of an interrupt to the start of the interrupt service routine
Scheduling is done so as to:
A: keep the waiting time the same
B: increase the waiting time
C: decrease the waiting time
D: none of the mentioned
C: decrease the waiting time
Each entry in a Translation lookaside buffer (TLB) consists of:
A: key
B: constant
C: value
D: bit value
A: key
The number of processes completed per unit time is known as:
A: Output
B: Capacity
C: Throughput
D: Efficiency
C: Throughput
The advantage of dynamic loading is that:
A: A used routine is used multiple times
B: CPU utilization increases
C: An unused routine is never loaded
D: All of the mentioned
C: An unused routine is never loaded
When a program tries to access a page that is mapped in address space but not loaded in physical memory, then:
A: segmentation fault occurs
B: no error occurs
C: fatal error occurs
D: page fault occurs
D: page fault occurs
What is the drawback of banker’s algorithm?
A: in advance processes rarely know that how much resource they will need
B: all of the mentioned
C: the number of processes changes as time progresses
D: resource once available can disappear
B: all of the mentioned
A Process Control Block(PCB) does not contain which of the following:
A: Bootstrap program
B: Stack
C: Data
D: Code
A: Bootstrap program
Each –?– has its own index block.
A: file
B: address
C: partition
D: all of the mentioned
A: file
Given a priori information about the –?– number of resources of each type that maybe requested for each process, it is possible to construct an algorithm that ensures that the system will never enter a deadlock state.
A: average
B: approximate
C: minimum
D: maximum
D: maximum
Physical memory is broken into fixed-sized blocks called:
A: backing store
B: pages
C: none of the mentioned
D: frames
D: frames
The resource allocation graph is not applicable to a resource allocation system:
A: none of the mentioned
B: with a single instance of each resource type
C: with multiple instances of each resource type
D: single & multiple instance of each resource type
C: with multiple instances of each resource type
The –?– time in a swap out of a running process and swap in of a new process into the memory is very high.
A: execution
B: waiting
C: all of the mentioned
D: context – switch
D: context – switch
How does the Hardware trigger an interrupt?
A: Executing a special program called interrupt program
B: Sending signals to CPU through system bus
C: Executing a special program called system program
D: Executing a special operation called system call
B: Sending signals to CPU through system bus
To access the services of operating system, the interface is provided by the:
A: System calls
B: Library
C: API
D: Assembly instructions
A: System calls
Which of the following is FALSE?
A: Blocking one kernel level thread blocks all other related threads
B: Related kernel level threads can be scheduled on different processors in a multiprocessor system
C: Context switch time is longer for kernel level threads than for user level threads
D: User level threads do not need any hardware support
A: Blocking one kernel level thread blocks all other related threads
Operating System maintains the page table for:
A: each thread
B: each process
C: each address
D: each instruction
B: each process
The disadvantage of invoking the detection algorithm for every request is:
A: all of the mentioned
B: overhead of the detection algorithm due to consumption of memory
C: excessive time consumed in the request to be allocated memory
D: considerable overhead in computation time
D: considerable overhead in computation time
Caching is –?– spooling.
A: all of the mentioned
B: same as
C: not the same as
D: none of the mentioned
C: not the same as
Effective access time is directly proportional to:
A: memory access time
B: page-fault rate
C: none of the mentioned
D: hit ratio
B: page-fault rate
Defective sectors on disks are often known as:
A: none of the mentioned
B: bad blocks
C: good blocks
D: destroyed blocks
B: bad blocks
What is interprocess communication?
A: communication within the process
B: none of the mentioned
C: communication between two process
D: communication between two threads of same process
C: communication between two process
For real time operating systems, interrupt latency should be:
A: maximum
B: zero
C: minimal
D: dependent on the scheduling
C: minimal
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
D: no matter which algorithm is used, it will always occur
In the –?– algorithm, the disk arm goes as far as the final request in each direction, then reverses direction immediately without going to the end of the disk.
A: C-LOOK
B: C-SCAN
C: SCAN
D: LOOK
D: LOOK
The operations that can be invoked on a condition variable are:
A: signal & hold
B: hold & wait
C: continue & signal
D: wait & signal
D: wait & signal
The real difficulty with SJF in short term scheduling is:
A: it is too complex to understand
B: it is too good an algorithm
C: knowing the length of the next CPU request
D: none of the mentioned
C: knowing the length of the next CPU request
A synchronious event that is generated when the processor detects a predefined condition is called a(n):
A: exception
B: page fault
C: interrupt
D: the IDT
A: exception
The operating system’s routines perform key support functions such as:
A: accepting and carrying out user commands
B: both
C: communicating with peripheral devices
B: both
In the Many to Many model true concurrency cannot be gained because:
A: none of the mentioned
B: the kernel can schedule only one thread at a time
C: there are too many threads to handle
D: it is hard to map threads with each other
B: the kernel can schedule only one thread at a time
A monitor is a type of:
A: high level synchronization construct
B: none of the mentioned
C: semaphore
D: low level synchronization construct
A: high level synchronization construct
Write ahead logging is a way:
A: to ensure atomicity
B: all of the mentioned
C: to keep data consistent
D: that records data on stable storage
B: all of the mentioned
What is trap door?
A: It is a Trojan horse
B: It is a virus which traps and locks user terminal
C: It is a hole in software left by designer
D: It is trap door in WarGames
C: It is a hole in software left by designer
Multimedia systems require –?– scheduling to ensure critical tasks will be serviced within timing deadlines.
A: normal
B: hard real time
C: none of the mentioned
D: soft real time
B: hard real time
In the tree structured directories:
A: the tree has the leaf directory
B: all of the mentioned
C: the tree has the stem directory
D: the tree has the root directory
D: the tree has the root directory
Under multiprogramming, turnaround time for short jobs is usually –?– and that for long jobs is slightly –?–
A: Shortened; Lengthened
B: Lengthened; Shortened
C: Shortened; Shortened
D: Shortened; Unchanged
A: Shortened; Lengthened
File virus attaches itself to the
A: all of the mentioned
B: source file
C: executable file
D: object file
C: executable file
When a web page is loading, and the user presses a button on the browser to stop loading the page:
A: the thread loading the page continues with the loading
B: the thread loading the page is paused
C: the thread loading the page does not stop, but continues with another task
D: the thread loading the page is cancelled
D: the thread loading the page is cancelled
The directory can be viewed as a –?– that translates file names into their directory entries.
A: swap space
B: cache
C: symbol table
D: partition
C: symbol table
The time taken for the desired sector to rotate to the disk head is called:
A: rotational latency
B: random access time
C: seek time
D: positioning time
A: rotational latency
When in contiguous allocation the space cannot be extended easily:
A: the file gets destroyed
B: the contents of the file have to be copied to a new space, a larger hole
C: the file will get formatted and lost all its data
D: none of the mentioned
B: the contents of the file have to be copied to a new space, a larger hole
Users and application programmers communicate with hardware through:
A: program instructions
B: a channel
C: the operating system
D: all of the mentioned
C: the operating system
What is a long-term scheduler?
A: None of the mentioned
B: It selects which process has to be brought into the ready queue
C: It selects which process to remove from memory by swapping
D: It selects which process has to be executed next and allocates CPU
B: It selects which process has to be brought into the ready queue
Anonymous access allows a user to transfer files:
A: only if he has an account on the remote system
B: without having an account on the remote system
C: none of the mentioned
D: only if he accesses the system with a guest account
B: without having an account on the remote system
Signals that occur at the same time, are presented to the process:
A: one at a time, in no particular order
B: none of the mentioned
C: all at a time
D: one at a time, in a particular order
A: one at a time, in no particular order
With round robin scheduling algorithm in a time shared system:
A: using very small time slices converts it into First come First served scheduling algorithm
B: using extremely small time slices increases performance
C: using very large time slices converts it into First come First served scheduling algorithm
D: using very small time slices converts it into Shortest Job First algorithm
C: using very large time slices converts it into First come First served scheduling algorithm
Memory management units:
A: increase the power consumption of the system
B: increase the cost of the system
C: increase the time required to complete an operation
D: all of the mentioned
D: all of the mentioned
A circular buffer:
A: all of the mentioned
B: overwrites older values as it goes
C: none of the mentioned
D: writes to the end of its space and then continues at the beginning
D: writes to the end of its space and then continues at the beginning
______ is an approach to restricting system access to authorized users.
A: Job-based access control
B: Role-based access control
C: None of the mentioned
D: Process-based access control
B: Role-based access control
The technique of duplicating every disk is known as:
A: shadowing
B: redundancy
C: mirroring
D: all of the mentioned
C: mirroring
Path names can be of two types:
A: absolute & relative
B: relative & local
C: global & relative
D: local & global
A: absolute & relative
When two users keep a subdirectory in their own directories, the structure being referred to is:
A: cyclic graph directory structure
B: acyclic graph directory
C: two level directory structure
D: tree structure
B: acyclic graph directory
What is not a good practice for user administration?
A: Isolating a system after a compromise
B: Perform random auditing procedures
C: Using telnet and FTP for remote access
D: Granting privileges on a per host basis
C: Using telnet and FTP for remote access
The size of a process is limited to the size of:
A: physical memory
B: external storage
C: secondary storage
D: none of the mentioned
A: physical memory
The child process completes execution,but the parent keeps executing, then the child process is known as:
A: Body
B: Zombie
C: Orphan
D: Dead
B: Zombie
The –?– table contains the base address of each page in physical memory.
A: page
B: frame
C: memory
D: process
A: page
For every process there is a:
A: all of the mentioned
B: page table
C: copy of page table
D: pointer to page table
B: page table
The segment base contains the:
A: starting physical address of the segment in memory
B: none of the mentioned
C: segment length
D: starting logical address of the process
A: starting physical address of the segment in memory
The host sets –?– bit when a command is available for the controller to execute.
A: status
B: command-ready
C: write
D: control
B: command-ready
If the resources are always preempted from the same process, –?– can occur.
A: deadlock
B: system crash
C: aging
D: starvation
D: starvation
In real time operating system:
A: a task must be serviced by its deadline period
B: process scheduling can be done only once
C: all processes have the same priority
D: kernel is not required
A: a task must be serviced by its deadline period
Which one of the following is the deadlock avoidance algorithm?
A: banker’s algorithm
B: round-robin algorithm
C: karn’s algorithm
D: elevator algorithm
A: banker’s algorithm
Data cannot be written to secondary storage unless written within a:
A: text format
B: swap space
C: file
D: directory
C: file
If one or more devices use a common set of wires to communicate with the computer system, the connection is called:
A: Bus
B: CPU
C: Wirefull
D: Monitor
A: Bus
Whenever a process needs I/O to or from a disk it issues a:
A: system call to the CPU
B: a special procedure
C: all of the mentioned
D: system call to the operating system
D: system call to the operating system
Virtual memory uses disk space as an extension of:
A: secondary storage
B: none of the mentioned
C: main memory
D: tertiary storage
C: main memory
A large number of disks in a system improves the rate at which data can be read or written:
A: if the disks are operated in parallel
B: if the disks are operated on sequentially
C: all of the mentioned
D: if the disks are operated on selectively
A: if the disks are operated in parallel
The signal operation of the semaphore basically works on the basic –?– system call.
A: getup()
B: wakeup()
C: continue()
D: start()
B: wakeup()
In linked allocation:
A: each file must occupy a set of contiguous blocks on the disk
B: none of the mentioned
C: all the pointers to scattered blocks are placed together in one location
D: each file is a linked list of disk blocks
D: each file is a linked list of disk blocks
Disks are segmented into one or more partitions, each containing a file system or:
A: made into backup space
B: made into swap space
C: left ‘raw’
D: left ‘ripe’
C: left ‘raw’
Using a pager:
A: decreases the swap time & amount of physical memory needed
B: increases the amount of physical memory needed
C: increases the swap time
D: decreases the swap time
A: decreases the swap time & amount of physical memory needed
The relocation register helps in:
A: protecting the address spaces of processes
B: none of the mentioned
C: a different address space to processes
D: providing more address space to processes
A: protecting the address spaces of processes
Which of the following do not belong to queues for processes?
A: PCB queue
B: Device Queue
C: Ready Queue
D: Job Queue
A: PCB queue
Windows NT uses a –?– implementation for I/O
A: message – passing
B: secondary memory
C: draft – passing
D: cache
A: message – passing
The operating system and the other processes are protected from being modified by an already running process because:
A: they have a protection algorithm
B: they are in different logical addresses
C: every address generated by the CPU is being checked against the relocation and limit registers
D: they are in different memory spaces
C: every address generated by the CPU is being checked against the relocation and limit registers
Which of the following calls never returns an error?
A: ioctl
B: getpid
C: fork
D: open
B: getpid
In SCSI disks used in high end PCs, the controller maintains a list of –?– on the disk. The disk is initialized during –?– formatting which sets aside spare sectors not visible to the operating system.
A: bad blocks, partitioning
B: destroyed blocks, partitioning
C: destroyed blocks, high level formatting
D: bad blocks, low level formatting
D: bad blocks, low level formatting
If a process needs I/O to or from a disk, and if the drive or controller is busy then:
A: the request will be placed in the queue of pending requests for that drive
B: the request will not be processed and will be ignored completely
C: none of the mentioned
D: the request will be not be placed
A: the request will be placed in the queue of pending requests for that drive
In addition to providing a user interface, the operating system:
A: manages system resources
B: complicates programming
A: manages system resources
Illegal addresses are trapped using the –?– bit.
A: error
B: protection
C: valid – invalid
D: access
C: valid – invalid
Working set model for page replacement is based on the assumption of:
A: locality
B: random access
C: modularity
D: globalization
A: locality
For Mutual exclusion to prevail in the system:
A: the processor must be a uniprocessor rather than a multiprocessor
B: at least one resource must be held in a non sharable mode
C: all of the mentioned
D: there must be at least one resource in a sharable mode
B: at least one resource must be held in a non sharable mode
A monitor is characterized by:
A: all of the mentioned
B: a set of programmer defined operators
C: an identifier
D: the number of variables in it
B: a set of programmer defined operators
Pages are swapped into and out from the real memory:
A: page pool
B: V-R area
C: partitions
D: paging device
A: page pool
In the non blocking send:
A: the sending process keeps sending until it receives a message
B: the sending process sends the message and resumes operation
C: none of the mentioned
D: the sending process keeps sending until the message is received
B: the sending process sends the message and resumes operation
CPU scheduling is the basis of:
A: larger memory sized systems
B: multiprocessor systems
C: none of the mentioned
D: multiprogramming operating systems
D: multiprogramming operating systems
If one thread opens a file with read privileges then:
A: any other thread can not read from that file
B: all of the mentioned
C: other threads in the same process can also read from that file
D: other threads in the another process can also read from that file
C: other threads in the same process can also read from that file
If the number of cycles spent busy – waiting is not excessive, then:
A: none of the mentioned
B: both programmed and interrupt driven I/O are equally efficient
C: interrupt driven I/O is more efficient than programmed I/O
D: programmed I/O is more efficient than interrupt driven I/O
D: programmed I/O is more efficient than interrupt driven I/O
Which one of the following is a process that uses the spawn mechanism to revage the system performance?
A: threat
B: worm
C: virus
D: trojan
B: worm
Time required to synchronous switch from the context of one thread to the context of another thread is called:
A: jitter
B: threads fly-back time
C: context switch time
D: none of the mentioned
C: context switch time
Which one of the following is a visual ( mathematical ) way to determine the deadlock occurrence?
A: inversion graph
B: starvation graph
C: none of the mentioned
D: resource allocation graph
D: resource allocation graph
For larger page tables, they are kept in main memory and a –?– points to the page table.
A: page table base pointer
B: page table base register
C: page table base
D: page table register pointer
B: page table base register
Why is it difficult to revoke capabilities?
A: They are distributed throughout the system
B: They are not defined precicely
C: None of the mentioned
D: They are too many
A: They are distributed throughout the system
A write of a block has to access:
A: a parity block
B: parity disk
C: all of the mentioned
D: the disk on which the block is stored
C: all of the mentioned
A deadlock can be broken by:
A: none of the mentioned
B: abort all the process in the system
C: preempt all resources from all processes
D: abort one or more processes to break the circular wait
D: abort one or more processes to break the circular wait
The open file table has a/an –?– associated with each file.
A: file content
B: file permission
C: close count
D: open count
D: open count
Process synchronization can be done on:
A: none of the mentioned
B: both hardware and software level
C: software level
D: hardware level
B: both hardware and software level
What is true about Indirection to revoke capability?
A: This system was adopted in MULTICS system
B: Capabilities point indirectly to the objects
C: Each capability will not have a unique entry in global
D: Table entries cannot be reused for other capabilities
B: Capabilities point indirectly to the objects
Optimal page – replacement algorithm is difficult to implement, because:
A: it requires a lot of information
B: it is extremely expensive
C: it is too complex
D: it requires future knowledge of the reference string
D: it requires future knowledge of the reference string
If the sum of the working – set sizes increases, exceeding the total number of available frames:
A: the operating system selects a process to suspend
B: then the process crashes
C: the system crashes
D: the memory overflows
A: the operating system selects a process to suspend
Suppose that a process is in “Blocked” state waiting for some I/O service. When the service is completed, it goes to the:
A: Suspended state
B: Ready state
C: Terminated state
D: Running state
B: Ready state
Some directory information is kept in main memory or cache to:
A: speed up access
B: increase free space in secondary storage
C: fill up the cache
A: speed up access
A better way of contiguous allocation to extend the file size is:
A: adding an extent (another chunk of contiguous space)
B: adding an index table to the first contiguous block
C: none of the mentioned
D: adding pointers into the first contiguous block
A: adding an extent (another chunk of contiguous space)
Which one of the following explains the sequential file access method?
A: read bytes one at a time, in order
B: read/write sequentially by record
C: read/write randomly by record
D: random access according to the given byte number
A: read bytes one at a time, in order
For swap space created in a separate disk partition where no file system or directory structure is placed, –?– used to allocate and deallocate the blocks.
A: normal file system routines can be
B: swap space storage manager is
C: special routines must be
D: normal file system routines cannot be
B: swap space storage manager is
A semaphore:
A: can be accessed from multiple processes
B: is a binary mutex
C: must be accessed from only one process
D: none of the mentioned
A: can be accessed from multiple processes
Thread pools help in:
A: servicing a single request using multiple threads from the pool
B: none of the mentioned
C: faster servicing of requests with an existing thread rather than waiting to create a new thread
D: servicing multiple requests using one thread
C: faster servicing of requests with an existing thread rather than waiting to create a new thread
What are the different ways to intrude?
A: Buffer overflows
B: All of the mentioned
C: Unexpected combinations and unhandled input
D: Race conditions
B: All of the mentioned
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 switches from the waiting state to the ready state
C: All of the mentioned
D: When a process goes from the running state to the waiting state
D: When a process goes from the running state to the waiting state
The problem of priority inversion can be solved by:
A: none of the mentioned
B: priority inversion protocol
C: both priority inheritance and inversion protocol
D: priority inheritance protocol
D: priority inheritance protocol
Memory protection in a paged environment is accomplished by:
A: restricted access rights to users
B: protection bit with each page
C: restriction on page visibility
D: protection algorithm with each page
B: protection bit with each page
Which one of the following is not true?
A: kernel is the program that constitutes the central core of the operating system
B: kernel remains in the memory during the entire computer session
C: kernel is the first part of operating system to load into memory during booting
D: kernel is made of various modules which can not be loaded in running operating system
D: kernel is made of various modules which can not be loaded in running operating system
–?– is generally faster than –?– and –?–
A: best fit, first fit, worst fit
B: none of the mentioned
C: worst fit, best fit, first fit
D: first fit, best fit, worst fit
D: first fit, best fit, worst fit
What is main objective of protection?
A: Ensure that each object is accessed correctly and only by allowed processes
B: Objects have different priority and thus different levels of protection
C: None of the mentioned
D: Ensure all objects are protected individually
A: Ensure that each object is accessed correctly and only by allowed processes
In general the two interrupt request lines are:
A: blocked & non maskable interrupts
B: none of the mentioned
C: maskable & non maskable interrupts
D: maskable & blocked interrupts
C: maskable & non maskable interrupts
On media that use constant linear velocity (CLV), the –?– is uniform.
A: density of bits per sector
B: the density of bits per track
C: none of the mentioned
D: density of bits on the disk
B: the density of bits per track
Another solution to the problem of external fragmentation problem is to:
A: permit smaller processes to be allocated memory at last
B: all of the mentioned
C: permit larger processes to be allocated memory at last
D: permit the logical address space of a process to be noncontiguous
D: permit the logical address space of a process to be noncontiguous
When a page fault occurs, the state of the interrupted process is:
A: saved
B: none of the mentioned
C: disrupted
D: invalid
A: saved
What does access matrix represent?
A: Rows-Domains, Columns-Objects
B: Rows-Objects, Columns-Domains
C: Rows-Domains, Columns-Access list
D: Rows-Access List, Columns-Domains
A: Rows-Domains, Columns-Objects
When one thread immediately terminates the target thread, it is called:
A: Systematic cancellation
B: Sudden Termination
C: Deferred cancellation
D: Asynchronous cancellation
D: Asynchronous cancellation
Which of the following system calls does not return control to the calling point, on termination?
A: ioctl
B: longjmp
C: exec
D: fork
C: exec
Paging increases the –?– time.
A: waiting
B: all of the mentioned
C: execution
D: context – switch
D: context – switch
For most computers, the bootstrap is stored in:
A: RAM
B: ROM
C: Tertiary storage
D: Cache
B: ROM
A fork system call will fail if:
A: all of the mentioned
B: the limit on the minimum number of processes that can be under execution by a single user would be executed
C: the previously executed statement is also a fork call
D: the limit on the maximum number of processes in the system would be executed
D: the limit on the maximum number of processes in the system would be executed
