OpSyst Final

RAID level ____ requires two different parity calculations.

6

The computer system ____ a file by activating the appropriate secondary storage device and loading the file into memory while updating its records of who is using that file.

Allocates

The ____ is a hardware flag that must be tested by the CPU to determine when a device has completed an operation.

Channel Status Word

A ____ of processing must be handled as a single unit.

Critical region

____ peripheral devices are assigned to only one job at a time.

Dedicated

The number of characters that can be recorded per inch on a magnetic tape is determined by the ____ of the tape.

Density

Device management principles are changing rapidly to accommodate cloud computing.

False

In general, operating systems must either choose avoidance or recovery as a strategy for dealing with deadlocks.

False

In parallel computations, mutual exclusion is achieved automatically because each operation is handled in order, one at a time.

False

RAID is a set of logical disk drives, viewed as a single physical unit by the operating system.

False

The Shortest Seek Time First device-scheduling algorithm moves the arm methodically from the inner to the outer track, servicing every request in its path.

False

The job of the I/O control unit is to keep up with the I/O requests from the CPU and pass them down the line to the appropriate control unit.

False

The two operations that can be performed on a semaphore variable are select and increment (P and V).

False

Which of the following is the first step in reducing a directed graph to eliminate deadlock?

Find a process that is currently using a resource and not waiting for one.

Most current operating systems support the implementation of threads, or ____, which have become part of numerous application packages.

Lightweight processes

____ is necessary in any computer system because some resources such as memory, CPU, and dedicated devices must be exclusively allocated to one user at a time.

Mutual exclusion

Fill in the missing event that causes deadlock in a database. There are two processes (P1 and P2), each of which needs to update two records (R1 and R2) and the following sequence leads to a deadlock: P1 accesses R1 and locks it. P2 accesses R2 and locks it. ____ P2 requests R1, which is locked by P1.

P1 requests R2, which is locked by P2.

Failure to lock database records before updating them may result in a ____ between processes.

Race

____ is a way to optimize search times on hard disk drives by ordering the requests once the read/write heads have been positioned

Rotational ordering

____ uses the same underlying philosophy as shortest job next, where the shortest jobs are processed first and longer jobs are made to wait.

SSTF

The I/O ____ allocates the devices, control units, and channels.

Scheduler

Of the three components of access time in a movable-head DASD, ____ is the slowest.

Seek time

A problem with test-and-set is that when many processes are waiting to enter a critical region, ____ can occur because the processes gain access in an arbitrary fashion.

Starvation

The ____ multiprocessing configuration is the most difficult to implement because the processes must be well synchronized to avoid races and deadlocks.

Symmetric

____ semaphores are used in the producer and consumer problem.

Three

Buffers are used to synchronize the movement of data between the relatively slow I/O devices and the very fast CPU.

True

Deadlock is a system-wide tangle of resource requests that begins when two or more jobs are put on hold, each waiting for a vital resource to become available.

True

If locks are not used to preserve data integrity, the updated records in a database may include only some of the data—and their contents depend on the order in which each process finishes its execution.

True

Nested RAID levels, also called hybrid levels, are complex RAID configurations created by combining multiple standard levels

True

Once starvation has been detected, an algorithm can be implemented in which the system blocks new jobs until the starving jobs have been satisfied.

True

Parallel processing is a situation in which two or more processors operate in one system at the same time and may or may not work on related activities.

True

Resource holding, where a job holds on to one resource while waiting for another one that's not yet available, can be sidestepped by forcing each job to request, at creation time, every resource it will need to run to completion.

True

The common element in all synchronization schemes is to allow a process to finish work on a critical region of the program before other processes have access to it.

True

When multiprocessing takes place at the thread level, a high degree of synchronization is required to disassemble each process.

True

When using the WAIT and SIGNAL operations, ____ sets the process's process control block to the blocked state and links it to the queue of processes waiting to enter this particular critical region.

WAIT

The primary disadvantage of contiguous storage is that ____.

a file can't be expanded unless there is empty space available immediately following it

A compressed image file can be reconstructed if a lossy compression algorithm is used because the compression process is reversible.

false

A field is a group of related records that can be identified by the user with a name, type, and size.

false

Files cannot be converted from sequential to direct or vice versa.

false

When a user gives a command to modify the contents of a file, it's actually a command to access folders within the file.

false

Within a file, variable-length records are easier to access directly than fixed-length records.

false

Many computer users and some operating systems call subdirectories ____.

folders

In a direct record organization scheme, the program used to store the data follows a set of instructions, called a ____ algorithm, that transforms each key into a number, the record's logical address.

hashing

When data is stored in fixed length fields, data that extends beyond the fixed size ____.

is truncated

On an optical disc, all sectors are ____.

of the same size throughout the disc

A UNIX or Linux system might identify a file as: /usr/imfst/flynn/inventory.doc. The first entry is a forward slash ( / ) representing the master directory, called the ____ directory.

root

Although a user directory is treated as a file, it is flagged to indicate to the File Manager that this file is really a ____ whose records are filenames that point to files.

subdirectory

Although noncontiguous allocation schemes eliminate external storage fragmentation and the need for compaction, they don't support direct access because there's no easy way to determine the exact location of a specific record.

true

Directories are special files that contain listings of filenames and their attributes.

true

When using a contiguous file storage scheme, the File Manager keeps track of empty storage areas by treating them as files.

true