Operating System

101. If a memory partition of size 80K is allocated to a process of size 60K then the 20K of the partition is wasted and cannot be allocated to any process. It is called _______.
यदि 80K की memory partition किसी 60K process को allocate की जाए और बची हुई 20K space किसी दूसरे process को न दी जा सके, तो इसे क्या कहते हैं?
(DSSSB TGT C.S. 01.08.2021 (Shift-II))
A. External fragmentation
B. Best fit
C. Worst fit
D. Internal fragmentation

Correct Answer: D

Explanation (EN): Unused space inside an allocated fixed partition is internal fragmentation.

Explanation (HI): Allocated fixed partition के भीतर बची हुई unused space internal fragmentation कहलाती है।

102. If two non-continuous free partitions of size 'a' and 'b' are available, a process of size 'c' cannot be allocated even when a + b > c, a < c and b < c. This problem is known as ______.
यदि 'a' और 'b' आकार की दो non-continuous free partitions उपलब्ध हों और a + b > c होने पर भी size 'c' का process allocate न हो सके, तो यह समस्या क्या कहलाती है?
(DSSSB TGT C.S. 01.08.2021 (Shift-II))
A. External fragmentation
B. Internal fragmentation
C. Quick fit
D. Worst fit

Correct Answer: A

Explanation (EN): When total free memory is enough but not contiguous, the problem is external fragmentation.

Explanation (HI): जब कुल free memory पर्याप्त हो लेकिन contiguous न हो, तब external fragmentation होती है।

103. The rate at which page fault occurs is known as _________.
जिस दर पर page faults होते हैं, उसे क्या कहते हैं?
(DSSSB TGT C.S. 01.08.2021 (Shift-II))
A. Swapping
B. Paging
C. Thrashing
D. Compaction

Correct Answer: C

Explanation (EN): Thrashing refers to very high page fault activity that severely reduces performance.

Explanation (HI): Thrashing बहुत अधिक page fault activity को दर्शाता है, जिससे performance बहुत गिर जाती है।

104. ______ is a process of lifting the process from memory and placing it on disk.
Memory से process को हटाकर disk पर रखने की प्रक्रिया क्या कहलाती है?
(DSSSB TGT C.S. 01.08.2021 (Shift-II))
A. Paging
B. Swapping out
C. Swapping in
D. Thrashing

Correct Answer: B

Explanation (EN): Moving a process from memory to disk is called swapping out.

Explanation (HI): Memory से process को disk पर भेजना swapping out कहलाता है।

105. Consider a main memory with the capacity of 4 page frames which are initially empty. If the page reference string is 1, 3, 4, 4, 3, 2, 1, 7, 5, 6 then what is the number of page fault using FIFO page replacement algorithm?
4 page frames वाली main memory शुरुआत में empty है। यदि page reference string 1, 3, 4, 4, 3, 2, 1, 7, 5, 6 हो, तो FIFO page replacement algorithm से कितने page faults होंगे?
(DSSSB TGT C.S. 01.08.2021 (Shift-II))
A. 6
B. 7
C. 8
D. 9

Correct Answer: B

Explanation (EN): FIFO simulation for the given string gives 7 page faults.

Explanation (HI): दिए गए string पर FIFO simulate करने पर 7 page faults आते हैं।

106. Which page replacement algorithm has Belady's anomaly?
Belady's anomaly किस page replacement algorithm में पाई जाती है?
(DSSSB TGT C.S. 01.08.2021 (Shift-II))
A. Optimal page replacement
B. FIFO page replacement
C. Least recently used page replacement
D. Not recently used page replacement

Correct Answer: B

Explanation (EN): Belady's anomaly is commonly associated with FIFO page replacement.

Explanation (HI): Belady's anomaly सामान्यतः FIFO page replacement algorithm में पाई जाती है।

107. If P is the mean of Poisson distribution, then what is the standard deviation?
यदि Poisson distribution का mean P है, तो standard deviation क्या होगी?
(DSSSB TGT C.S. 01.08.2021 (Shift-II))
A. P²
B. √P
C. P2
D. √P

Correct Answer: D

Explanation (EN): For a Poisson distribution, variance equals mean, so standard deviation is the square root of the mean.

Explanation (HI): Poisson distribution में variance mean के बराबर होती है, इसलिए standard deviation mean का square root होती है।

108. Which of the following is not a state of a process in operating system?
निम्न में से कौन-सी operating system में process की state नहीं है?
(DSSSB TGT C.S. 08.08.2021 (Shift-I))
A. Waiting
B. Excite
C. Running
D. Ready

Correct Answer: B

Explanation (EN): 'Excite' is not a valid process state.

Explanation (HI): 'Excite' operating system में process की valid state नहीं है।

109. Which of the following does not interrupt a running process?
निम्न में से कौन running process को interrupt नहीं करता?
(UGC NET C.S. December-2024)
A. Device
B. Timer
C. Scheduler
D. Power Failure

Correct Answer: C

Explanation (EN): The scheduler decides execution order but is not itself an interrupt source.

Explanation (HI): Scheduler execution order तय करता है, लेकिन स्वयं interrupt source नहीं होता।

110. Which of the following is the correct sequence with regard to service routine? A. Save contents of processor registers B. Turn the interrupt facility on C. Service the device whose flag is set D. Check which flag is set E. Restore contents of processor registers
Service routine के संबंध में सही sequence कौन-सा है? A. Processor registers के contents save करना B. Interrupt facility on करना C. जिस device का flag set है उसे service करना D. कौन-सा flag set है यह check करना E. Processor registers के contents restore करना
(UGC NET C.S. December-2024)
A. A, B, C, D, E
B. D, B, C, A, E
C. D, C, B, E, A
D. A, D, C, E, B

Correct Answer: D

Explanation (EN): The correct service routine sequence is save context, identify source, service device, restore context, then enable interrupts.

Explanation (HI): सही sequence है: context save करना, source पहचानना, device service करना, context restore करना, फिर interrupts enable करना।