Operating System MCQs with Answers
Practice important Operating System MCQs with answers and explanations.
Multiple Choice Questions
Q1001: Which of the following best describes a page fault?
- A: A memory access error
- B: A situation where a page is accessed but is not in memory
- C: A failure to load a program into memory
- D: An address error that leads to process termination
View Answer
B
Q1002: Which bit in the page table entry indicates whether a page is in memory?
- A: Valid bit
- B: Invalid bit
- C: Access bit
- D: Page fault bit
View Answer
A
Q1003: The page table is used to map logical memory to which type of memory?
- A: Physical memory
- B: Virtual memory
- C: Secondary memory
- D: Cache memory
View Answer
A
Q1004: When a page fault occurs, which component of the system performs the paging operation?
- A: CPU
- B: Operating system
- C: Disk controller
- D: Memory manager
View Answer
B
Q1005: What is the role of the valid-invalid bit in paging systems?
- A: It indicates whether a page is in memory or on disk
- B: It marks a page as read-only
- C: It locks a page in memory
- D: It determines the access level of a page
View Answer
A
Q1006: Which type of memory is typically used as secondary memory in demand paging?
- A: RAM
- B: Disk
- C: CPU cache
- D: Virtual memory
View Answer
B
Q1007: The term "lazy swapper" in demand paging refers to which process?
- A: Swapping out pages that are not used
- B: Swapping entire processes into memory
- C: Bringing pages into memory only when required
- D: Moving pages into memory before execution
View Answer
C
Q1008: In demand paging, the system swaps in pages from disk when needed and avoids swapping which pages?
- A: All pages
- B: Only needed pages
- C: Unused pages
- D: Pages from memory-mapped files
View Answer
B
Q1009: A page fault trap is caused when the system attempts to access which of the following?
- A: A page that is not in memory
- B: A page that is marked as valid
- C: A page that is already in memory
- D: A page that is locked
View Answer
A
Q1010: When a page fault occurs, which of the following is the first step in handling the fault?
- A: Read the page from disk
- B: Check the page's status
- C: Save the CPU's state
- D: Schedule a disk operation
View Answer
B