Operating System

61. In distributed system, the capacity of a system to adapt the increased service load is called_____
Distributed system में बढ़े हुए service load को adapt करने की क्षमता क्या कहलाती है?
(UGC NET C.S. November-2017 (Paper-II))
A. Tolerance
B. Scalability
C. Capability
D. Loading

Correct Answer: B

Explanation (EN): Scalability is the ability of a system to handle increased load.

Explanation (HI): Scalability किसी system की बढ़े हुए load को handle करने की क्षमता है।

62. In _____ disk scheduling algorithm, the disk head moves from one end to other end of the disk, serving the request along the way. When the head reaches the other end, it immediately returns to the beginning of the disk without serving any requests on the return trip.
किस disk scheduling algorithm में disk head एक छोर से दूसरे छोर तक जाते हुए requests serve करता है और दूसरे छोर पर पहुँचकर return trip में requests serve किए बिना शुरू में वापस लौट जाता है?
(UGC NET C.S. November-2017 (Paper-II))
A. LOOK
B. SCAN
C. C-LOOK
D. C-SCAN

Correct Answer: B

Explanation (EN): According to the given source, this behavior is identified as SCAN.

Explanation (HI): दिए गए source के अनुसार इस behavior को SCAN कहा गया है।

63. Suppose there are six files F1, F2, F3, F4, F5, F6 with corresponding sizes 150 KB, 225 KB, 75 KB, 60 KB, 275 KB and 65 KB respectively. The files are to be stored on a sequential device in such a way that optimizes access time. In what order should the files be stored?
मान लीजिए छह files F1, F2, F3, F4, F5, F6 के sizes क्रमशः 150 KB, 225 KB, 75 KB, 60 KB, 275 KB और 65 KB हैं। यदि इन्हें sequential device पर access time optimize करने के लिए store करना हो, तो order क्या होगा?
(UGC NET C.S. November-2017 (Paper-II))
A. F5, F2, F1, F3, F6, F4
B. F4, F6, F3, F1, F2, F5
C. F1, F2, F3, F4, F5, F6
D. F6, F5, F4, F3, F2, F1

Correct Answer: B

Explanation (EN): To optimize access time, smaller files are arranged earlier as per the given source, yielding the order F4, F6, F3, F1, F2, F5.

Explanation (HI): दिए गए source के अनुसार access time optimize करने के लिए files का सही order F4, F6, F3, F1, F2, F5 होगा।

64. Which module gives control of the CPU to the process selected by the short-term scheduler?
Short-term scheduler द्वारा selected process को CPU का control कौन-सा module देता है?
(UGC NET C.S. November-2017 (Paper-II))
A. Dispatcher
B. Interrupt
C. Scheduler
D. Threading

Correct Answer: A

Explanation (EN): The dispatcher gives CPU control to the process selected by the short-term scheduler.

Explanation (HI): Dispatcher short-term scheduler द्वारा selected process को CPU का control देता है।

65. Two atomic operations permissible on Semaphores are _____ and _____.
Semaphores पर permissible दो atomic operations कौन-सी हैं?
(UGC NET C.S. November-2017 (Paper-II))
A. Wait, stop
B. Wait, hold
C. Hold, signal
D. Wait, signal

Correct Answer: D

Explanation (EN): The two atomic operations on semaphores are wait and signal.

Explanation (HI): Semaphores पर दो atomic operations wait और signal हैं।

66. Match List-I with List-II. A. First Come First Served (FCFS) B. Shortest Job First (SJF) C. Round Robin (RR) D. Priority Scheduling
List-I और List-II का मिलान कीजिए: A. FCFS, B. SJF, C. Round Robin, D. Priority Scheduling
(UGC NET C.S. Re-Exam June-2024)
A. A-II, B-III, C-IV, D-I
B. A-II, B-IV, C-III, D-I
C. A-III, B-IV, C-II, D-I
D. A-III, B-IV, C-I, D-II

Correct Answer: C

Explanation (EN): FCFS → order of arrival, SJF → smallest next burst time, Round Robin → fair allocation by time slice, Priority Scheduling → each process assigned a priority.

Explanation (HI): FCFS → arrival order, SJF → smallest next burst time, Round Robin → time slice द्वारा fair allocation, Priority Scheduling → प्रत्येक process को priority दी जाती है।

67. A multiprocessor system with 16 processors is used to execute a parallelizable task. If the serial portion of the task takes 200 clock cycles and the parallel portion takes 800 clock cycles, when all 16 processors are used how many total clock cycles are required to complete the task?
16 processors वाले multiprocessor system में एक parallelizable task execute किया जाता है। यदि task का serial portion 200 clock cycles लेता है और parallel portion 800 clock cycles लेता है, तो सभी 16 processors उपयोग होने पर total clock cycles कितने होंगे?
(UGC NET C.S. Re-Exam June-2024)
A. 250
B. 300
C. 400
D. 450

Correct Answer: A

Explanation (EN): Parallel portion time = 800/16 = 50 cycles. Total = 200 + 50 = 250 cycles.

Explanation (HI): Parallel portion का time = 800/16 = 50 cycles। कुल time = 200 + 50 = 250 cycles।

68. Which of the following statements are TRUE about mutual exclusion in concurrent programming? A. Mutual exclusion ensures that only one process can be in a critical section at any given time. B. Mutual exclusion is designed to prevent conflicts and ensure that only one process can access shared resources at a time. C. Mutual exclusion can use various algorithms to ensure that processes do not enter the critical section simultaneously. D. Mutual exclusion allows multiple processes to access the critical section simultaneously to improve performance.
Concurrent programming में mutual exclusion के बारे में निम्न statements में कौन-से true हैं? A. किसी भी समय केवल एक process critical section में हो सकता है। B. Mutual exclusion conflicts रोकने और shared resources पर एक समय में एक process की access सुनिश्चित करने के लिए है। C. यह विभिन्न algorithms का उपयोग कर सकता है ताकि processes एक साथ critical section में प्रवेश न करें। D. यह performance सुधारने के लिए multiple processes को एक साथ critical section में आने देता है।
(UGC NET C.S. Re-Exam June-2024)
A. (A), (B), (C) Only
B. (B), (C), (D) Only
C. (B), (D), (A) Only
D. (A), (C), (D) Only

Correct Answer: A

Explanation (EN): Statements A, B and C are true; D is false because mutual exclusion does not allow simultaneous access to the critical section.

Explanation (HI): Statements A, B और C सही हैं; D गलत है क्योंकि mutual exclusion critical section में simultaneous access की अनुमति नहीं देता।

69. Which of the following statements are TRUE about Privileged Instructions? A. It can only be executed by the Operating System kernel and not by user applications. B. It is designed to perform operations that can directly affect the hardware or system state such as I/O operations or changing memory management setting. C. User application can execute privileged instructions if they have the correct permissions, set by the Operating System. D. It usually executed in user mode to ensure the safety and security of the system.
Privileged Instructions के बारे में निम्न statements में कौन-से true हैं? A. इन्हें केवल OS kernel execute कर सकता है, user applications नहीं। B. ये hardware या system state को directly affect करने वाले operations जैसे I/O या memory management settings बदलने के लिए होते हैं। C. User applications सही permissions होने पर privileged instructions execute कर सकती हैं। D. ये सामान्यतः user mode में execute होते हैं।
(UGC NET C.S. Re-Exam June-2024)
A. (A) and (B) Only
B. (A), (B) and (C) Only
C. (B) and (C) Only
D. (B), (C) and (D) Only

Correct Answer: A

Explanation (EN): Only A and B are true. Privileged instructions execute in kernel mode, not user mode, and user applications cannot directly execute them.

Explanation (HI): केवल A और B सही हैं। Privileged instructions kernel mode में execute होते हैं, user mode में नहीं, और user applications इन्हें सीधे execute नहीं कर सकतीं।

70. There are three processes P1, P2 and P3 sharing a semaphore for synchronizing a variable. Initial value of semaphore is one. Assume that negative value of semaphore tells us how many processes are waiting in queue. Processes access the semaphore in following order: (A) P2 needs to access (B) P1 needs to access (C) P3 needs to access (D) P2 exits critical section (E) P1 exits critical section. The final value of semaphore will be:
तीन processes P1, P2 और P3 एक semaphore share कर रहे हैं। Semaphore का initial value 1 है। मान लें negative value waiting processes की संख्या बताती है। यदि access order (A) P2 needs to access, (B) P1 needs to access, (C) P3 needs to access, (D) P2 exits critical section, (E) P1 exits critical section है, तो semaphore का final value क्या होगा?
(UGC NET C.S. June-2017 (Paper-II))
A. 0
B. 1
C. -1
D. -2

Correct Answer: A

Explanation (EN): Starting from 1: P2 makes it 0, P1 makes it -1, P3 makes it -2, P2 exit makes it -1, P1 exit makes it 0.

Explanation (HI): Initial value 1 से शुरू करें: P2 के बाद 0, P1 के बाद -1, P3 के बाद -2, P2 exit के बाद -1, और P1 exit के बाद 0।