Operating Systems

1. Which of the following best describes virtual memory?

• It is a part of main memory only used for swapping

• It is a technique to execute processes that may not be completely in memory

• It is used to increase the size of physical memory

• It is the same as RAM

In paging, the page table maps:

• Logical addresses to physical addresses

• Physical addresses to logical addresses

• Virtual memory to RAM

• RAM to secondary storage

Which of the following is NOT a page replacement algorithm?

• FIFO

• LRU

• Optimal

• SSTF

Thrashing occurs when:

• Processes are swapping too frequently between memory and disk

• The CPU usage is 100%

• There is no virtual memory

• Processes are blocked

What is the role of the Translation Lookaside Buffer (TLB)?

• Stores the actual data of pages

• Improves the performance of segmentation

• Maps logical to virtual addresses

• Caches page table entries for fast retrieval

Which of the following is NOT a valid file allocation method?

• Contiguous

• Linked

• Indexed

• Direct

Which of the following file access methods allows reading records in any order?

• Sequential

• Direct

• Indexed Sequential

• Linear

In a typical file system, the structure of directories is usually:

• Linear

• Tree

• Graph

• Circular

The main goal of disk scheduling algorithms is to:

• Improve CPU utilization

• Reduce seek time

• Maximize I/O throughput

• All of the above

Which of the following manages the allocation of disk blocks and free space in a file system?

• File control block

• Directory structure

• Free-space manager

• Disk controller