Operating systems (CSE) test-2

Software may trigger an interrupt by executing a special operation called___

 

• System Call

• Event Handling   

• Interrupt Servicing

• Loader

Answer explanation

Software triggers an interrupt using a System Call, which is a special operation that requests services from the operating system. This is essential for managing hardware and software interactions.

Which is not the state of a process ?

• Running 

• Killed

• Waiting 

• Ready

Answer explanation

The 'Killed' state is not a standard state of a process. The typical states include Running, Waiting, and Ready, which describe the process's current activity or status in the system.

_____time is the interval from the time of transmission of a process to the time of completion

• Turn Around

• Running

• Waiting

• Execution

Answer explanation

Turn Around time refers to the total time taken from the initiation of a process until its completion, encompassing both execution and waiting periods. It is the correct choice as it captures the entire interval described.

_______CPU scheduling algorithm suffers from starvation

• FCFS

• Priority

• Time sharing

• Round Robin

Answer explanation

The Priority CPU scheduling algorithm can lead to starvation, where lower-priority processes may never get executed if higher-priority processes keep arriving. In contrast, FCFS, Time sharing, and Round Robin do not suffer from this issue.

Operations of a semaphore are

• Wait & Signal

• Push & Pull

• Add & Sub

• Hold & wait

Answer explanation

The operations of a semaphore are 'Wait' and 'Signal'. 'Wait' decreases the semaphore value, blocking if it is zero, while 'Signal' increases it, potentially waking up waiting processes. This is essential for process synchronization.

The purpose of banker’s algorithm  is_____  

• Deadlock Recovery 

• Deadlock Avoidance

• Deadlock Prevention

• No preemption

Answer explanation

The banker’s algorithm is designed to avoid deadlock by ensuring that resource allocation does not lead to a situation where processes are waiting indefinitely. Thus, the correct answer is Deadlock Avoidance.

Which of the memory allocation scheme is faster ?

• First Fit

• Best Fit

• Worst Fit  

• Paging

Answer explanation

First Fit is faster because it allocates the first available block of memory that is large enough, minimizing search time. In contrast, Best Fit and Worst Fit require more time to search for the optimal block, making them slower.

Paging suffers from

• Internal Fragmentation

• External Fragmentation

• Starvation

• Belady’s  Anomaly

Answer explanation

Paging suffers from external fragmentation because it can lead to free memory being split into small, non-contiguous blocks, making it difficult to allocate larger contiguous memory spaces, even if total free memory is sufficient.

_____RAID level refers to disk mirroring

• Level 0

• Level 1

• Level 2

• Level 3

Answer explanation

RAID Level 1 refers to disk mirroring, where data is duplicated on two or more disks for redundancy. This ensures data availability in case one disk fails, making Level 1 the correct answer.

A time sharing system has ________

• More than one program in the system

• More than one memory in the system

• More than one task at a time, each task getting same amount of time to execute

• More than on processor in the system

Answer explanation

A time sharing system allows multiple tasks to run concurrently, giving each task a fair share of CPU time. This ensures efficient use of resources and responsiveness, making 'more than one task at a time, each task getting same amount of time to execute' the correct choice.