Operating Systems Final (Multiple Choice Questions)

___ is a symmetric block encryption algorithm

AES

___ is/are not a technique for passing parameters from an application to a system call.

Cache memory

Which of the following would be an acceptable signal handling scheme for a multi-threaded program?

Deliver the signal to the thread to which the signal applies. Deliver the signal to every thread in the process. Deliver the signal to only certain threads in the process. (Its all the above)

Policy ___.

Determines what will be done

Which of the following would lead you to believe that a given system is an SMP type system?

Each processor can perform all tasks within the operating system.

Which of the following scheduling algorithms is always non-preemptive?

FCFS

What is the purpose of the mutex semaphore in the implementation of the bounded-buffer problem using semaphores?

It ensures mutual exclusion to the shared buffer pool.

A calling java thread becomes the owner of a lock when ___.

It enters a synchronized method.

On time slicing systems, a runnable Java thread will continue executing until which of the following events occurs?

Its time quantum expires, its exits its run() method, or it blocks for I/O (Any events A through C.)

Suppose a process using semaphores does a release() operation before executing its critical section and an acquire() operation afterward, instead of the other way around. What may happen due to this error?

Multiple processes could be in their critical sections simultaneously

___ is a symmetric stream block encryption algorithm

RC4

___ scheduling is approximated by predicting the next CPU burst with an exponential average of the measured lengths of previous CPU bursts.

SJF

___ is a technique for managing bad blocks that maps a bad sector to a spare sector.

Sector sparing

___ provide(s) an interface to the services by an operating system.

System calls

___ occurs when a process spends more time paging than executing.

Thrashing

A code segment that misuses its environment is called a ___.

Trojan horse

To the SYSGEN program of an operating system, the least useful piece of information is ___.

What applications to install

Which of the following is true of the Java programming language in relation to protection?

When a class is loaded, the JVM assigns the class to a protection domain that gives the permissions of that class.

___ is the dynamic storage-allocation algorithm which results in the largest leftover hole in memory.

Worst fit

In a system resource-allocation graph, ___.

a directed edge from a process to a resource is called a request edge

A(n) ___ matches the process with each entry in the TLB.

address-space identifier

A denial of service attack is ___.

aimed at disrupting legitimate use of a system

An instruction that executes atomically ___.

all of the above (must consist of only one machine instruction, executes as a single, uninterruptible unit, cannot be used to solve the critical section problem)

A solution to the critical section problem does not have to satisfy which of the following requirements?

atomicity

Transfers between memory and disk are performed a ___.

block at a time

A ___ saves the state of the currently running process and restores the state of the next process to run.

context switch

Which of the following allocation methods ensures that only one access is needed to get a disk block using direct access?

contiguous allocation

Worms ___.

continue to grow as the internet expands.

In an access matrix, the ___ right allows a process to change the entries in a row.

control

The ___ occurs in first come first served scheduling when a process with a long CPU burst occupies the CPU.

convoy effect

A(n) ___ refers to where a process is accessing/uipdating shared data.

critical section

In Linux and other UNIX-based operating systems, which of the following is not considered a classification of users in connection with each file?

current user

A ___ is a public key digitally signed by a trusted party.

digital certificate

A(n) ___ is a custom build of the Linux operating system.

distribution

A deadlocked state occurs whenever ___.

every process in a set is waiting for an event that can only be caused by another process in the set

A(n) ___ is used in many file systems at the end of a file name to indicate the type of the file.

extension

Belady's anomaly is the observation that ___.

for some PRAs, the page-fault may increase as number of allocated frames increases.

The Windows CreateProcess() system call creates a new process. What is the equivalent system call in UNIX?

fork()

The ___ implementation of an access table consists of sets of ordered triples.

global table

One necessary condition for deadlock is ___, which states that a process must be holding one resource and waiting to acquire additional resources.

hold and wait

The most common technique for writing multithreaded Java programs is _____.

implementing the Runnable interface and defining its run() method

A process control block ___.

includes information on the process's state

A(n) ___ page table has on page entry for each physical frame of memory.

inverted

Thread specific data is data that ___.

is copied and not shared with the parent process

Optimal page replacement ___.

is used mostly for comparison with other page-replacement schemes

A spinlock ___.

is useful when locks are expected to be held for a short amount of time

Which of the following is the simplest method for implementing a directory?

linear list

The file-allocation table (FAT) used in MS-DOS is a modified version of ___.

linked allocation

An address generated by a CPU is referred to as a ___.

logical address

The ___ multithreading model multiplexes a number of user level threads to a lesser or equal number of kernel threads.

many to many

LWP is ___.

placed between user and kernel threads

To handle deadlocks, operating systems most often ___.

pretend that deadlocks never occur

Embedded computers typically run a ___ operating system.

real-time

A race condition ___.

results when several threads try to access and modify the same data concurrently

What are the two largest components of positioning time for a disk?

seek time + rotational latency

A(n) ____ is a buffer that holds output for a device that cannot accept interleaved data streams.

spool

In a paired-password system, ___.

the computer supplies one part of a password and the user enters the other part

In an environment where several processes may open the same file at the same time, ___

the operating system typically uses two internal tables called the system-wide and per disk tables to keep track of open files

A ___ uses an existing thread --- rather than creating a new one --- to complete a task.

thread pool

The default scheduling class for a process in Solaris is ___.

time sharing

In the UNIX operating system, a domain is associated with the ___.

user-id

A disk with free blocks 0, 1, 5, 9, 15 would be represented with what bit map?

1100010001000001

Consider a logical address with a page size of 32 KB. How many bits must be used to represent the page offset in the logical address?

15

Suppose a program is operating with execution-time binding and the physical address generated is 600. The relocation register is set to 250. What is the corresponding logical address?

350