OS Day 2 part 2

What is virtual memory?

• Memory that is physically present in the system

• Memory that is used only by virtual machines

• Memory that can be used as an extension of RAM

• Memory that can only be accessed by the kernel

What is demand paging?

• A method of paging that loads pages into memory as they are needed

• A method of paging that loads all pages into memory at once

• A method of paging that uses a fixed amount of memory

• A method of paging that requires additional hardware support

What is page replacement?

• A technique used to load pages into memory

• A technique used to swap pages in and out of memory

• A technique used to allocate memory

• A technique used to manage virtual memory

What is the purpose of page replacement algorithms?

• To ensure that all pages are loaded into memory

• To prevent thrashing

• To maximize the number of pages in memory

• To decide which pages to remove from memory when space is needed

Which of the following is not a page replacement algorithm?

• First-In, First-Out (FIFO)

• Least Recently Used (LRU)

• Most Recently Used (MRU)

• Shortest Job First (SJF)

Which page replacement algorithm suffers from Belady's Anomaly?

• FIFO

• LRU

• MRU

• Optimal

Which page replacement algorithm can suffer from starvation?

• FIFO

• LRU

• MRU

• Optimal

What is the drawback of the FIFO page replacement algorithm?

• It can lead to thrashing

• It does not take into account the time since a page was last accessed

• It requires hardware support

• It is not optimal

What is the drawback of the LRU page replacement algorithm?

• It can suffer from Belady's Anomaly

• It requires knowledge of future page requests

• It is not practical to implement

• It can be computationally expensive

Which page replacement algorithm is similar to the FIFO algorithm, but includes a second chance for pages that are still in use

• LRU

• Clock

• MRU

• Optimal