Q#1: Virtual memory allows:
(A) Execution of processes without loading entire program into main memory
(B) Only CPU optimization
(C) Only cache usage
(D) Only disk management
Answer: (A) Execution of processes without loading entire program into main memory
Q#2: Virtual memory is implemented using:
(A) Paging or segmentation
(B) Only contiguous allocation
(C) Only cache
(D) Only CPU registers
Answer: (A) Paging or segmentation
Q#3: Demand paging means:
(A) Loading pages into memory only when required
(B) Loading entire process
(C) Only CPU scheduling
(D) Only disk allocation
Answer: (A) Loading pages into memory only when required
Q#4: Page fault occurs when:
(A) Required page is not in main memory
(B) CPU idle
(C) Memory is full
(D) Disk failure
Answer: (A) Required page is not in main memory
Q#5: Virtual address refers to:
(A) Address generated by CPU
(B) Physical memory address
(C) Disk address
(D) Cache line
Answer: (A) Address generated by CPU
Q#6: Physical address refers to:
(A) Actual location in main memory
(B) Virtual address
(C) Disk address
(D) Cache line
Answer: (A) Actual location in main memory
Q#7: Page table stores:
(A) Mapping from virtual to physical addresses
(B) CPU registers
(C) Disk blocks
(D) Cache lines
Answer: (A) Mapping from virtual to physical addresses
Q#8: Page table base register (PTBR) stores:
(A) Starting address of the page table
(B) CPU register
(C) Disk block number
(D) Cache address
Answer: (A) Starting address of the page table
Q#9: Page table entry (PTE) contains:
(A) Frame number, valid/invalid bit, protection bits
(B) Only CPU register
(C) Only cache line
(D) Only disk block
Answer: (A) Frame number, valid/invalid bit, protection bits
Q#10: Valid/invalid bit in PTE indicates:
(A) Whether page is in main memory or not
(B) CPU busy or idle
(C) Memory full
(D) Disk busy
Answer: (A) Whether page is in main memory or not
Q#11: Frame is:
(A) Fixed-size block of physical memory
(B) Page table entry
(C) Disk block
(D) CPU register
Answer: (A) Fixed-size block of physical memory
Q#12: Page is:
(A) Fixed-size block of logical memory
(B) Physical memory frame
(C) Disk sector
(D) CPU register
Answer: (A) Fixed-size block of logical memory
Q#13: Page size is usually:
(A) Power of 2, e.g., 4 KB, 8 KB
(B) Random size
(C) CPU register size
(D) Disk block size
Answer: (A) Power of 2, e.g., 4 KB, 8 KB
Q#14: Page replacement is required when:
(A) A page fault occurs and memory is full
(B) CPU idle
(C) Disk failure
(D) Cache miss
Answer: (A) A page fault occurs and memory is full
Q#15: FIFO page replacement replaces:
(A) The oldest loaded page
(B) The most recently used page
(C) Random page
(D) Page with smallest number
Answer: (A) The oldest loaded page
Q#16: LRU (Least Recently Used) replaces:
(A) Page that has not been used for the longest time
(B) Oldest page
(C) Random page
(D) CPU register
Answer: (A) Page that has not been used for the longest time
Q#17: Optimal page replacement replaces:
(A) Page that will not be used for the longest future time
(B) Oldest page
(C) Random page
(D) Most recently used page
Answer: (A) Page that will not be used for the longest future time
Q#18: Thrashing occurs when:
(A) Too many page faults slow down system
(B) CPU idle
(C) Memory full
(D) Disk failure
Answer: (A) Too many page faults slow down system
Q#19: Working set of a process is:
(A) Set of pages a process is currently using
(B) CPU registers
(C) Disk blocks
(D) Cache lines
Answer: (A) Set of pages a process is currently using
Q#20: Locality of reference means:
(A) Programs access a small set of pages repeatedly
(B) CPU idle
(C) Memory full
(D) Disk busy
Answer: (A) Programs access a small set of pages repeatedly
Q#21: TLB (Translation Lookaside Buffer) stores:
(A) Recent page table entries
(B) CPU registers
(C) Disk blocks
(D) Cache lines
Answer: (A) Recent page table entries
Q#22: TLB reduces:
(A) Time required for virtual address translation
(B) CPU usage
(C) Disk access
(D) Memory allocation
Answer: (A) Time required for virtual address translation
Q#23: Multi-level page tables reduce:
(A) Memory required to store page tables
(B) CPU utilization
(C) Disk usage
(D) Cache memory
Answer: (A) Memory required to store page tables
Q#24: Inverted page table stores:
(A) One entry per frame instead of per process page
(B) CPU registers
(C) Disk block mapping
(D) Cache lines
Answer: (A) One entry per frame instead of per process page
Q#25: Segmentation divides memory into:
(A) Logical units like code, data, stack
(B) Fixed-size pages
(C) CPU registers
(D) Disk blocks
Answer: (A) Logical units like code, data, stack
Q#26: Paging suffers from:
(A) Internal fragmentation
(B) External fragmentation
(C) CPU idle
(D) Disk failure
Answer: (A) Internal fragmentation
Q#27: Segmentation suffers from:
(A) External fragmentation
(B) Internal fragmentation
(C) CPU idle
(D) Disk failure
Answer: (A) External fragmentation
Q#28: Page fault handling involves:
(A) Saving state, loading page from disk, updating page table, resuming process
(B) CPU idle
(C) Memory allocation
(D) Disk reset
Answer: (A) Saving state, loading page from disk, updating page table, resuming process
Q#29: Dirty bit indicates:
(A) Page has been modified
(B) Page is valid
(C) CPU idle
(D) Disk full
Answer: (A) Page has been modified
Q#30: Clean page means:
(A) Page has not been modified
(B) Page invalid
(C) CPU idle
(D) Disk busy
Answer: (A) Page has not been modified
Q#31: Memory-mapped files use:
(A) Virtual memory to access disk files
(B) CPU registers
(C) Only cache
(D) Only disk sectors
Answer: (A) Virtual memory to access disk files
Q#32: Copy-on-write technique delays:
(A) Copying pages until they are modified
(B) Page loading
(C) CPU scheduling
(D) Disk allocation
Answer: (A) Copying pages until they are modified
Q#33: Shared pages reduce:
(A) Memory usage by multiple processes
(B) CPU usage
(C) Disk usage
(D) Cache usage
Answer: (A) Memory usage by multiple processes
Q#34: Page table base register contains:
(A) Base address of page table in memory
(B) CPU register
(C) Disk block
(D) Cache line
Answer: (A) Base address of page table in memory
Q#35: Multi-level page table avoids:
(A) Large contiguous memory allocation for page table
(B) CPU scheduling
(C) Disk allocation
(D) Cache line usage
Answer: (A) Large contiguous memory allocation for page table
Q#36: Virtual memory allows:
(A) Multiprogramming with limited physical memory
(B) Only single program execution
(C) Only CPU optimization
(D) Only cache usage
Answer: (A) Multiprogramming with limited physical memory
Q#37: Effective access time (EAT) depends on:
(A) Memory access time and page fault rate
(B) Only CPU speed
(C) Only disk speed
(D) Only cache size
Answer: (A) Memory access time and page fault rate
Q#38: Page replacement algorithms aim to:
(A) Minimize page faults
(B) Only CPU utilization
(C) Only memory allocation
(D) Only disk scheduling
Answer: (A) Minimize page faults
Q#39: FIFO page replacement may suffer from:
(A) Belady’s anomaly
(B) Optimal page replacement
(C) LRU anomaly
(D) CPU idle
Answer: (A) Belady’s anomaly
Q#40: Belady’s anomaly occurs when:
(A) Increasing number of frames increases page faults
(B) Decreasing frames increases page faults
(C) CPU idle
(D) Disk full
Answer: (A) Increasing number of frames increases page faults
Q#41: LRU can be implemented using:
(A) Counters or stack
(B) CPU registers
(C) Disk blocks
(D) Cache lines
Answer: (A) Counters or stack
Q#42: Thrashing reduces:
(A) CPU utilization
(B) Memory usage
(C) Disk speed
(D) Cache speed
Answer: (A) CPU utilization
Q#43: Local replacement algorithm replaces pages:
(A) From the current process only
(B) From any process
(C) CPU registers
(D) Disk blocks
Answer: (A) From the current process only
Q#44: Global replacement algorithm replaces pages:
(A) From any process
(B) Only current process
(C) CPU registers
(D) Disk blocks
Answer: (A) From any process
Q#45: Virtual memory improves:
(A) System performance and process management
(B) Only CPU usage
(C) Only memory allocation
(D) Only disk usage
Answer: (A) System performance and process management
Q#46: Dirty page is written back to disk when:
(A) It is replaced in memory
(B) CPU idle
(C) Disk full
(D) Cache cleared
Answer: (A) It is replaced in memory
Q#47: Pre-paging loads:
(A) Pages predicted to be used soon
(B) Entire process
(C) CPU registers
(D) Disk blocks
Answer: (A) Pages predicted to be used soon
Q#48: Page fault rate increases when:
(A) Too few frames allocated to process
(B) CPU idle
(C) Disk full
(D) Cache full
Answer: (A) Too few frames allocated to process
Q#49: Effective use of virtual memory requires:
(A) Good page replacement algorithm and sufficient memory
(B) CPU only
(C) Disk only
(D) Cache only
Answer: (A) Good page replacement algorithm and sufficient memory
Q#50: Main goal of virtual memory:
(A) Execute large programs with limited physical memory
(B) Only CPU optimization
(C) Only memory allocation
(D) Only disk management
Answer: (A) Execute large programs with limited physical memory