Operating System MCQs

When a process begins execution with no pages in memory?

When the page fault rate is low ____________

Locality of reference implies that the page reference being made by a process ____________

Which of the following page replacement algorithms suffers from Belady’s Anomaly?

A process refers to 5 pages, A, B, C, D, E in the order : A, B, C, D, A, B, E, A, B, C, D, E. If the page replacement algorithm is FIFO, the number of page transfers with an empty internal store of 3 frames is?

A process refers to 5 pages, A, B, C, D, E in the order : A, B, C, D, A, B, E, A, B, C, D, E. If the page replacement algorithm is FIFO, the number of page frames is increased to 4, then the number of page transfers ____________

A memory page containing a heavily used variable that was initialized very early and is in constant use is removed, then the page replacement algorithm used is ____________

A virtual memory system uses First In First Out (FIFO) page replacement policy and allocates a fixed number of frames to a process. Consider the following statements. P : Increasing the number of page frames allocated to a process sometimes increases the page fault rate Q : Some programs do not exhibit locality of reference Which of the following is TRUE?

Users _______ that their processes are running on a paged system.

When a page is selected for replacement, and its modify bit is set ____________

The aim of creating page replacement algorithms is to ____________

A FIFO replacement algorithm associates with each page the _______

What is the Optimal page – replacement algorithm?

Optimal page – replacement algorithm is difficult to implement, because ____________

LRU page – replacement algorithm associates with each page the ______

What are the two methods of the LRU page replacement policy that can be implemented in hardware?

When using counters to implement LRU, we replace the page with the ____________

In the stack implementation of the LRU algorithm, a stack can be maintained in a manner ____________

There is a set of page replacement algorithms that can never exhibit Belady’s Anomaly, called ____________

Applying the LRU page replacement to the following reference string. 12452124 The main memory can accommodate 3 pages and it already has pages 1 and 2. Page 1 came in before page 2. How many page faults will occur?

Increasing the RAM of a computer typically improves performance because ____________

The essential content(s) in each entry of a page table is/are ____________

What is the reason for using the LFU page replacement algorithm?

What is the reason for using the MFU page replacement algorithm?

The implementation of the LFU and the MFU algorithm is very uncommon because ____________

The minimum number of frames to be allocated to a process is decided by the ____________

When a page fault occurs before an executing instruction is complete if ____________

Consider a machine in which all memory reference instructions have only one memory address, for them we need at least _____ frame(s).

The maximum number of frames per process is defined by ____________

The algorithm in which we split m frames among n processes, to give everyone an equal share, m/n frames is known as ____________

The algorithm in which we allocate memory to each process according to its size is known as ____________

_________ replacement allows a process to select a replacement frame from the set of all frames, even if the frame is currently allocated to some other process.

_________ replacement allows each process to only select from its own set of allocated frames.

One problem with the global replacement algorithm is that ____________

________ replacement generally results in greater system throughput.

A process is thrashing if ____________

Thrashing _______ the CPU utilization.

What is a locality?

When a subroutine is called ____________

A program is generally composed of several different localities, which _____ overlap.

In the working set model, for: 261577775162341234443434441323 if DELTA = 10, then the working set at time t1 (….7 5 1) is?

If working set window is too small ____________

If working set window is too large ____________

If the sum of the working – set sizes increases, exceeding the total number of available frames ____________

Consider the following page reference string. 12342156212376321236 For LRU page replacement algorithm with 4 frames, the number of page faults is?

Consider the following page reference string. 12342156212376321236 For LRU page replacement algorithm with 5 frames, the number of page faults is?

Consider the following page reference string. 12342156212376321236 For FIFO page replacement algorithms with 4 frames, the number of page faults is?

Consider the following page reference string. 12342156212376321236 For Optimal page replacement algorithms with 3 frames, the number of page faults is?

______ is a unique tag, usually a number identifies the file within the file system.

To create a file ____________