Which of the following is not a function of an Operating System?Which of the following is not a function of an Operating System?Process ManagementCompilation of ProgramsFile ManagementC. Compilation of ProgramsCompiling programs is a task of compilers, not the OS. OS handles memory, processes, files, and I/O devices.
Which OS scheduling algorithm gives first come, first served basis?Round RobinSJFFCFSPriorityC) FCFSFirst Come, First Served executes processes in the order they arrive.
Thrashing in OS is caused by:Low CPU utilizationExcessive pagingDeadlockHigh CPU utilizationB) Excessive pagingThrashing happens when most of the CPU time is spent on swapping pages.
Which memory management technique uses fixed-size blocks?PagingSegmentationVirtual MemorySwappingA) PagingPaging divides memory into fixed-size blocks called pages and frames.
Critical Section problem is associated with:DeadlockSynchronizationInterrupt handlingFile managementB) SynchronizationCritical section problem ensures mutual exclusion for shared resources.
Round Robin scheduling is best suited for:Batch systemsInteractive systemsReal-time systemsMultiprocessor systemsB) Interactive systemsRound Robin provides time-sharing, making it ideal for interactive environments.
Which of the following is responsible for process scheduling in an OS?CompilerCPU SchedulerFile ManagerDevice DriverB) CPU SchedulerCPU Scheduler selects from the ready queue which process should be executed next by the CPU.
Which memory management technique allows a process to be broken into non-contiguous parts?Contiguous AllocationPagingFixed PartitioningSwappingB) PagingPaging divides processes and memory into fixed-size pages and frames, allowing non-contiguous allocation.
A deadlock can occur if which of the following conditions hold simultaneously?Mutual Exclusion, Hold & Wait, No Preemption, Circular WaitMutual Exclusion, Paging, Multiprogramming, ContentionSwapping, Paging, Scheduling, SynchronizationOnly MultiprogrammingA) Mutual Exclusion, Hold & Wait, No Preemption, Circular WaitThese four Coffman conditions must all be present for a deadlock to occur.
Which of the following is not an OS type?BatchTime-sharingMultiprogrammingAssemblyD) AssemblyAssembly is a programming language, not an operating system type.
Which scheduling algorithm gives the minimum average waiting time?FCFSRound RobinShortest Job NextPriority SchedulingC) Shortest Job NextShortest Job Next minimizes average waiting time by executing the shortest processes first.
Thrashing in OS occurs when:Too many files are openedCPU utilization is very highToo much time is spent swapping pagesSystem is running in real-time modeC) Too much time is spent swapping pagesThrashing occurs when the system spends more time paging than executing processes.
Which algorithm is used for page replacement?LRUDijkstraRound RobinBellman-FordA) LRULeast Recently Used (LRU) replaces the page that has not been used for the longest time.
Semaphore is used for:Memory managementProcess synchronizationFile allocationDeadlock prevention onlyB) Process synchronizationSemaphores prevent race conditions by controlling process access to shared resources.
Which memory is fastest in a computer system?Virtual MemoryCache MemoryMain MemorySecondary MemoryB) Cache MemoryCache memory is small but extremely fast, storing frequently accessed data for quick retrieval.
The Banker’s Algorithm is used for:Memory Allocation: CPU SchedulingDeadlock AvoidancePage ReplacementC) Deadlock AvoidanceBanker’s algorithm ensures safe resource allocation to prevent deadlocks.
Context switching happens when:A process completesCPU switches from one process to anotherMemory is swappedAn interrupt is ignoredB) CPU switches from one process to anotherContext switching saves the state of the current process and loads the next.
Which file allocation method uses linked list of blocks?Contiguous AllocationLinked AllocationIndexed AllocationHashed AllocationB) Linked AllocationLinked allocation links blocks using pointers to store files non-contiguously.
Virtual memory allows:Larger logical memory than physical memoryDirect hardware accessFastest executionDisable pagingA) Larger logical memory than physical memoryVirtual memory uses disk space to extend physical RAM.
Belady’s anomaly is related to:CPU SchedulingPage Fault RateDeadlocksDisk SchedulingB) Page Fault RateBelady’s anomaly occurs when increasing frames increases page faults in FIFO replacement.
Which of the following is a non-preemptive scheduling algorithm?Round RobinShortest Remaining Time FirstFCFS (First Come First Serve)Priority with PreemptionC) FCFS (First Come First Serve)FCFS allows process to run until it finishes, no preemption.
Demand paging loads pages:At program startOnly when neededIn sequential orderRandomlyB) Only when neededDemand paging brings pages into memory only when accessed.
Belady’s anomaly is seen in:Optimal page replacementLRU page replacementFIFO page replacementLFU page replacementC) FIFO page replacementFIFO may cause page faults to increase as frames increase.
Semaphore is used for:Process SynchronizationCPU SchedulingMemory AllocationDeadlock Detection OnlyA) Process SynchronizationSemaphores coordinate access to shared resources.
Context switching occurs during:I/O OperationProcess State ChangePower FailureCache MissB) Process State ChangeContext switch saves current process state and loads next process state.
Which scheduling algorithm may lead to starvation?FCFSRound RobinPriority SchedulingSJFC) Priority SchedulingLow-priority processes may starve if higher-priority tasks keep arriving.
Which memory management scheme allows processes to move between partitions?Fixed PartitioningSwappingPagingSegmentationB) SwappingSwapping moves processes in and out of memory dynamically.
Thrashing occurs when:CPU overheatsToo many processes run simultaneouslyExcessive paging occursCache misses happenC) Excessive paging occursThrashing happens when most CPU time is spent on paging rather than execution.
UNIX is an example of:Batch OSTime-Sharing OSReal-Time OSEmbedded OSB) Time-Sharing OSUNIX supports multi-user, time-sharing functionality.
Page replacement algorithms are used in:CPU SchedulingVirtual Memory ManagementFile SystemsDevice DriversB) Virtual Memory ManagementThey decide which page to replace when a page fault occurs.
Deadlock can be prevented by:Mutual exclusionCircular waitPreemptionSafe state schedulingD) Safe state schedulingOperating systems prevent deadlock by resource allocation in safe states.
Thrashing occurs due to:Too much CPU utilizationExcessive pagingDeadlockCache missB) Excessive pagingThrashing happens when CPU spends more time swapping pages than executing.
Which system call creates a new process in UNIX?exec()fork()wait()exit()B) fork()fork() creates a new process by duplicating the parent process.
Semaphore is used for:Memory allocationSynchronizationFile handlingInterrupt handlingB) SynchronizationSemaphores prevent race conditions in critical sections.
Which scheduling algorithm may cause starvation?FCFSRound RobinPriority SchedulingShortest Job NextC) Priority SchedulingLow-priority processes may never get CPU time.
Page replacement policy with least number of page faults is:FIFOLRUOptimalRandomC) OptimalOptimal replacement replaces the page that will not be used for the longest period.
Deadlock requires all of the following except:Mutual exclusionHold and waitPreemptionCircular waitC) PreemptionPreemption prevents deadlock, so it is not a required condition.
Thrashing occurs when:CPU utilization is highMemory is underutilizedExcessive page swapping happensDisk scheduling failsC) Excessive page swapping happensThrashing reduces performance by constant page swapping.
Which is not a real-time OS?Windows CEVxWorksLinux with RT patchMS-DOSD) MS-DOSMS-DOS cannot guarantee timing constraints.
Which scheduling algorithm gives minimum average waiting time?FCFSSJFRound RobinPriorityB) SJFShortest Job First minimizes average waiting time.
In demand paging, a page fault occurs when:Page is in memoryPage is not in memoryDisk is fullCache is emptyB) Page is not in memoryA page fault happens when required data is not in RAM.
Which is not a valid disk scheduling algorithm?FCFSSSTFSCANB-TreeD) B-TreeB-Trees are a data structure, not a disk scheduling method.
Virtual memory is implemented using:CacheSegmentationPagingBoth B and CD) Both B and CVirtual memory can use paging or segmentation.
Which command lists active processes in UNIX?listprocpstasklistjobsB) psThe ps command displays process status.
Round Robin scheduling is best for:Batch systemsReal-time systemsTime-sharing systemsMultiprocessingC) Time-sharing systemsRR ensures fairness in time-sharing OS.
Which is not an OS function?Memory managementProcess schedulingApplication developmentFile managementC) Application developmentOS supports applications but doesn’t build them.
Deadlock prevention can be done by:Mutual exclusionCircular waitPreemptionResource holdingC) PreemptionPreemption breaks deadlock conditions.
Thrashing occurs due to:High CPU usageExcessive pagingDisk failureDeadlockB) Excessive pagingThrashing slows system as CPU spends time swapping pages.
Which algorithm avoids starvation?FCFSSJFRound RobinPriority schedulingC) Round RobinEvery process gets equal time slices.
Which scheduling algorithm is starvation-free?FCFSRound RobinPriority SchedulingShortest Job FirstB) Round RobinRound Robin ensures fairness by giving each process equal CPU time.
A page fault occurs when:Page is found in cachePage is found in main memoryPage is not found in memoryPage is replacedC) Page is not found in memoryPage faults happen when required pages are not in physical memory.
Which OS structure provides highest modularity?MonolithicMicrokernelLayeredBatchB) MicrokernelMicrokernels provide modularity and better maintainability.
Which of the following is NOT a deadlock condition?Mutual exclusionHold and waitPreemptionCircular waitC) PreemptionPreemption prevents deadlock by forcibly releasing resources.
Which scheduling algorithm minimizes average waiting time?FCFSRound RobinShortest Job FirstPriority SchedulingC) Shortest Job FirstSJF schedules shortest processes first, reducing waiting time.
In paging, the mapping of virtual addresses to physical addresses is done by:CPUPage tableCacheRegisterB) Page tableThe page table translates virtual to physical addresses.
Which system call is used to create a new process in UNIX?exec()fork()wait()clone()B) fork()fork() creates a new child process.
The Banker’s algorithm is used for:Memory allocationDeadlock avoidanceCPU schedulingFile managementB) Deadlock avoidanceBanker’s algorithm allocates resources safely to avoid deadlocks.
Swapping refers to:CPU schedulingMoving processes between memory and diskMultiprogrammingProcess creationB) Moving processes between memory and diskSwapping moves processes between main memory and secondary storage.
In which scheduling algorithm can starvation occur?FCFSSJFRound RobinPriorityD) PriorityLower-priority processes may starve if high-priority keep arriving.
The working set model is used in:CPU schedulingDeadlock detectionMemory managementDisk schedulingC) Memory managementIt defines pages a process needs to minimize faults.
Which OS concept ensures multiple processes do not interfere with each other’s memory?VirtualizationPagingProtectionDeadlockC) ProtectionProtection ensures isolation among processes.
The Banker's algorithm is used for:Page replacement Deadlock avoidanceCPU schedulingFile allocationB) Deadlock avoidanceIt checks resource allocation to avoid unsafe states.
In an OS, thrashing is caused by:Too many I/O requestsExcessive context switchingInsufficient main memoryDeadlocksC) Insufficient main memoryThrashing occurs when the system spends more time swapping than executing.
Which OS component acts as an interface between hardware and user programs?ShellKernelDevice DriverFile ManagerB) KernelThe kernel directly manages hardware resources.
What does a page table store?Process IDsLogical to physical address mappingInstructionsI/O requestsB) Logical to physical address mappingPage tables translate virtual addresses.
Which memory allocation suffers from both internal and external fragmentation?PagingSegmentationContiguous allocationVirtual memoryC) Contiguous allocationBoth types of fragmentation occur in contiguous memory.
Which scheduling algorithm gives equal time to all processes?SJFPriorityRound RobinFCFSC) Round RobinRR assigns fixed time slices to processes.
Deadlock requires all except:Mutual ExclusionHold and WaitPreemptionCircular WaitC) PreemptionDeadlocks occur in absence of preemption.
Virtual memory is implemented using:RegistersCacheDisk StorageRAM onlyC) Disk StorageVirtual memory uses disk as extension of RAM.
In UNIX, which command lists all processes?lspspwdcatB) psps shows active processes.
Thrashing in an OS occurs when?CPU overheatsExcessive context switching happensProcesses spend more time paging than executingDeadlock occursC) Processes spend more time paging than executingThrashing reduces performance due to excessive page faults.
Which file system is used in Linux?FAT32NTFSext4HFS+C) ext4ext4 is the default file system in most Linux distributions.
What does the "semaphore" control in OS?Memory AllocationProcess SynchronizationFile ManagementDeadlock DetectionB) Process SynchronizationSemaphores prevent race conditions by managing resource access.
