Q31. [GATE 2015] Multilevel Feedback Queue me kaunsa queue sabse high priority pe hota hai?Answer: Shortest Burst Time wala / System Process queue
Solution: MLFQ me system processes ko highest priority milti hai, fir interactive, fir batch. Jo process TQ pura use kar le use neeche wale queue me bhej dete hain.
Q32. [GATE 2016] Multilevel Queue Scheduling me starvation ko kaise roka jaata hai?Answer: Aging aur Queue me time-slicing se
Solution: Har queue ko CPU time ka kuch % milta hai (e.g. 80% foreground, 20% background) taaki low queue bhi starve na kare.
Q33. [GATE 2018] Aging ka main use kya hai?
Answer: Starvation ko hatana
Solution: Waiting time ke saath priority increase karna = Aging. Low priority process bhi ek din high ban jayega.
Q34. [GATE 2019] Multilevel Feedback Queue me ek new process kaha aayega?
Answer: Topmost Queue me
Solution: Rule 1 of MLFQ – Har new process top queue me aata hai. Agar TQ me complete nahi hua to next lower queue me jaata hai.
Q35. [GATE 2020] 3 Queues Q0(TQ=8), Q1(TQ=16), Q2(FCFS). P1=20, P2=40. Completion order?
Answer: P1 pehle, fir P2
Solution: P1 -> Q0 me 8 bacha 12 -> Q1 me 16 bacha 0 nahi 4 bacha -> Q1 me hi 4. P2 ko zyada time lagega to Q2 tak jayega.
Q36. [GATE 2021] Which is TRUE for Multilevel Feedback Queue?
(a) It is preemptive (b) It allows process to move between queues (c) It is starvation freeAnswer: (a) and (b) are TRUE
Solution: MLFQ preemptive hota hai aur process queues ke beech move karta hai. Lekin bina Aging ke starvation ho sakta hai, so (c) false.
Q37. [GATE 2022] Priority Inversion ko solve karne ka tarika?Answer: Priority Inheritance Protocol
Solution: Low priority process jab high priority ke resource ko lock kare to uski priority temporarily high kar do. Ye Multilevel me kaam aata hai.
Q38. [GATE 2023] Aging ka formula kaunsa hota hai?Answer: New Priority = Old Priority + (Waiting Time * Aging Factor)
Solution: Har kuch time baad priority = priority + waiting. Factor 0.5, 1 etc le sakte hain.
Q39. [GATE 2024] 2 Level Queue – Foreground RR(TQ=4) 80%, Background FCFS 20%. Is this starvation free?Answer: YES, starvation free hai
Solution: Kyunki Background ko bhi 20% CPU time fixed mila hai, isliye chahe foreground me kitne bhi process ho, background ko bhi chance milega.
Q40. [GATE 2025] MLFQ me agar saare processes I/O bound hain to kya hoga?Answer: Saare top queue me hi rahenge, performance badhiya hogi
Solution: I/O bound process jaldi I/O pe chale jaate hain, TQ pura use nahi karte, isliye demote nahi hote. Isliye response time achha rehta hai.