Question 1

Although the Banker's Algorithm has been used to avoid deadlocks in systems with a few resources,it isn't practical for most systems.

Accepted Answer

The Banker's Algorithm is complex and requires significant overhead, making it impractical for larger systems with numerous resources.

Question 2

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.

Accepted Answer

Without locks, multiple processes can simultaneously access and modify the same data, leading to data inconsistencies and unpredictable results. Locking ensures that only one process can modify a particular piece of data at a time, preserving data integrity. Without locks, the order in which processes finish their execution determines which changes to the data are ultimately committed and can result in incomplete or incorrect data.

Question 3

One problem with the Banker's Algorithm is that because the algorithm assumes the worst case,vital resources can be unavailable in order to guard against unsafe states.

Accepted Answer

The Banker's Algorithm is designed to prevent deadlock by assuming the worst-case scenario, which can lead to some resources being unavailable even when they are actually available. This can cause unnecessary delays and resource wastage.

Question 4

All recovery algorithms have one feature in common: they all require at least one victim,which,when removed from the deadlock,will free the system.

Accepted Answer

Recovery algorithms are designed to break deadlocks and allow the system to continue functioning. However, in order to do so, they need to remove at least one process or resource from the deadlock, which can be considered a "victim" of the situation. Without a victim to release, recovery algorithms would not be able to resolve deadlocks.

Question 5

To recover from deadlock,a factor that is commonly considered when selecting a victim is the CPU time used by a job - jobs close to completion are usually left alone.

Accepted Answer

This is true, as selecting a job that is close to completion can help to minimize the overall impact on system performance and reduce the time needed to resolve the deadlock.

Question 6

In the dining philosophers problem,there are five philosophers and four forks.

Accepted Answer

In the dining philosophers problem, there are five philosophers and five forks, with each philosopher needing two forks to eat.

Question 7

A livelock can be caused by two processes accessing different areas of the same disk.

Accepted Answer

A livelock can occur when two or more processes are waiting for each other to release a resource, such as a disk lock. In this case, the processes are accessing different areas of the same disk, but they are still dependent on each other to release the locks they are holding. This can lead to a situation where neither process can make progress, and the system becomes deadlocked.

Question 8

When using the Banker's Algorithm,an operating system must be sure never to satisfy a request that moves it from a safe state to an unsafe one.

Accepted Answer

This statement is true. The Banker's Algorithm is designed to ensure that the system remains in a safe state by not granting requests that could result in an unsafe state. This is done by considering each request and simulating its execution to see if it results in a safe state or not. If the request leads to an unsafe state, it is not granted.

Question 9

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.

Accepted Answer

This approach prevents deadlocks by ensuring that a job only starts if it can obtain all necessary resources, thus avoiding the situation where it holds onto some resources while waiting for others.

Question 10

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

Accepted Answer

Operating systems can implement a combination of avoidance, prevention, and detection/recovery strategies to deal with deadlocks, not just a single approach.

Question 11

When using a directed graph to model a system,if there's a cycle in the graph,then there is a deadlock involving the processes and the resources shown in the cycle.

Accepted Answer

In a directed graph, a cycle indicates a situation where a set of processes or resources are waiting for each other to complete, which can lead to a deadlock. Therefore, if there is a cycle in the graph, there is a possibility of a deadlock occurring in the system.

Question 12

A deadlock is preceded by the simultaneous occurrence of six conditions that the operating system (or other systems)could have recognized.

Accepted Answer

A deadlock is typically characterized by the simultaneous occurrence of four conditions: mutual exclusion, hold and wait, no preemption, and circular wait. These conditions must all be present for a deadlock to occur.

Question 13

Starvation is the result of a policy that liberally allocates resources.

Accepted Answer

Starvation is usually the result of a lack of resources, particularly food, rather than a policy of liberal resource allocation. Liberal resource allocation may lead to other issues such as overconsumption, but not necessarily starvation.

Question 14

According to the Banker's Algorithm,an unsafe state always leads to deadlock.

Accepted Answer

An unsafe state is not guaranteed to lead to a deadlock; it simply means that there is a possibility that a sequence of allocations could lead to a situation where no progress is possible, but it does not ensure that a deadlock will occur.

Question 15

Fixing a deadlock situation requires outside intervention.

Accepted Answer

Deadlock situations occur when two or more processes are unable to proceed because they are waiting for each other to release resources. This can only be resolved through external intervention, such as a system administrator or a specialized software tool designed to detect and resolve deadlocks.

Question 16

Deadlock does not usually affect the entire system.

Accepted Answer

Deadlock can potentially affect the entire system as it can cause the affected processes to become unresponsive and occupy system resources, leading to a slowdown or even a complete halt in the system.

Question 17

A race introduces the element of chance,which is a highly desirable attribute,in database management.

Accepted Answer

In database management, a race condition introduces unpredictability and can lead to data corruption or loss, which is undesirable.

Question 18

Database locking should be done only at the level of the entire database.

Accepted Answer

Database locking can be done at different levels such as row level, page level, and table level along with the entire database level. The level of locking required depends on the application and database design.

Question 19

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.

Accepted Answer

This is an accurate definition of deadlock.

Question 20

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

Accepted Answer

This is correct as blocking new jobs until the starving jobs are satisfied is a technique to prevent or mitigate starvation in a system.

Quiz 5: Process Synchronization