Recent questions and answers in Operating System - GATE CSE Doubts

0 votes

0 answers

Self-Doubt- Disk Schedulling
A program of size 64 MB is stored on disk which supports an average seek time of 32ms and rotation time of 20ms . Page size is 4MB and track size is 32MB . If the page of the program are countiguously placed on DIsk then the toatal time ... program-from-disk Someone kindly have a look at it, and tell me/us which one is the right approach to solve such questions.

asked 4 hours ago in Operating System by HeartBleed (52 points) | 12 views

0 votes

0 answers

Operating System -Self Doubt
What is meaning of Page Address? How it’s size could be similar to PTE size?

asked 11 hours ago in Operating System by srestha (318 points) | 15 views

0 votes

1 answer

Dispatcher Self Doubt
The dispatcher program runs in user mode or kernel mode?

answered 1 day ago in Operating System by Priyansh Singh (41 points) | 17 views

+1 vote

2 answers

Gatebook Test series:Operating System
Suppose an OS using fair share scheduling : that is users are guaranteed to get their fair-share of the CPU time. Consider the following scenario. User 1 has four processes P1, P2, P3 and P4, and user 2 has only 1 process P5. All processes arrive at the same time ... 24 (A) 24 (B) 21.5 (C) 22 (D) 23.5 Please someone having any idea for this question, Do tell !!

answered 2 days ago in Operating System by Satbir (2.5k points) | 49 views

0 votes

1 answer

gatebook #file system
Consider a UNIX file system with 12 direct pointers, 1 indirect pointer, 1 double-indirect pointer, and 1 triple-indirect pointer in the i-node. Assume that disk blocks are 8K bytes and that each pointer to a disk block requires 4 bytes.How many disk reads will ... i-nodes and no data blocks); Assume that the root directory contains very few entries (i.e., is one block long) .

answered 4 days ago in Operating System by Satbir (2.5k points) | 13 views

0 votes

0 answers

Self-Doubt-- Fork Address Printing
MY QUESTION IS 1)WHY PRINTF() PRINT VIRTUAL ADDRESS(MENTIONED IN EXPLANTION) NOT PHYSICAL ADDRESS 2) WHY VIRTUAL ADDRESS(O/P OF PRINTF(&VAR)) OF A VARIABLE CHANGES WHEN WE RUN A PROGRAM MANY TIMES Consider the following code fragment: ... in child process. Therefore, we get same addresses in both parent and child. https://gateoverflow.in/84315/fork-system-call

asked 5 days ago in Operating System by HeartBleed (52 points) | 12 views

0 votes

1 answer

#gatebooktestseries( PAGING)
Consider a virtual memory system that uses paging. The page size in this system is 256 . Each individual page table fits exactly into one memory frame, and the size of each page table entry (PTE) is . Suppose that there is a process with a virtual address space of the maximum size. How many bytes of memory are occupied by the page tables for this process ?

answered 5 days ago in Operating System by Shaik Masthan (227 points) | 18 views

0 votes

2 answers

MADE EASY: OPERATING SYSTEM
Consider a system using demand paging architecture where it take 3 ms to service a page fault if either empty frame is available or replaced page is not to be modified and takes 10 ms if the replaced page is modified. Main memory access time is 1 ms ... page fault rate to get the effective memory access time not more than 4 ms is ________ (%). (Upto 2 decimal places)

answered 6 days ago in Operating System by Mk Utkarsh (153 points) | 45 views

0 votes

0 answers

Doubt OS ACE test series 2020
Which of the following events does not affect a process in the running state? Interrupt exit i/o event scheduler dispatcher correct answer mentioned is option (D) and the reason they gave is the process is in running state and scheduler dispatcher is ... round,,,like moving from running to ready also or it only does the job of moving from ready to running state?

asked 6 days ago in Operating System by Priyansh Singh (41 points) | 17 views

0 votes

0 answers

doubt OS ace test 2020
ANSWER is given as 4 .. i want to ask is there any less time consuming way of approaching such questions.. or is it the same method try different different combinations of program in preemption.

asked 6 days ago in Operating System by Priyansh Singh (41 points) | 20 views

+1 vote

0 answers

OS made easy 2020
I wanna talk about the option (C), how it is satisfying Bounded waiting… what if p1 completes execution and again runs… so we can’t really say there is any kind of bounded waiting .. or am i approaching it in a wrong way.

asked Oct 14 in Operating System by Priyansh Singh (41 points) | 18 views

+1 vote

1 answer

Maximum number of process required in one processor

answered Oct 14 in Operating System by tp21 (11 points) | 22 views

0 votes

0 answers

doubt operating system ACE (2019)

asked Oct 13 in Operating System by Priyansh Singh (41 points) | 22 views

0 votes

0 answers

Doubt operating system ace
When an interrupt or a system call transfers control to OS from a process? A separate kernel stack is used from the stack of interrupted process. Stack of interrupted process only used always Every time a new stack is created on the top of the stack of the interrupted process None of the above.

asked Oct 13 in Operating System by Priyansh Singh (41 points) | 5 views

0 votes

1 answer

Doubt Operating system
Consider a program with 5 pages and reference string w= 1 2 3 4 1 2 5 1 2 3 4 5 Which of the following pages are not victims if FIFO page replacement is used on three frames? 1 2 5 2 3 5 1 2 3 4 what does here “pages are not victims if FIFO is used “ means?

answered Oct 13 in Operating System by Pratyush Priyam Kuan (72 points) | 12 views

0 votes

0 answers

Doubt Operating system
Consider a binary search algorithm to search an element in array of ‘n’ numbers.Assume that this array spans over multiple pages with each page holding ‘p’ elements (n>p). Every memory access will generate a page fault until the search range is less than ‘p’. The minimum value of ‘p’ that reduces the page fault is? 1 n log(n) 1/n

asked Oct 12 in Operating System by Priyansh Singh (41 points) | 13 views

0 votes

0 answers

Doubt Operating system
Suppose you know that there will only be 4 processes running at the same time, each with a Resident Set Size (RSS) of 512 MB and a working set size of 256 KB. Assuming the same system with 32 bit Virtual and Physical address space with 4KB page size ... entries that your system would need to support to be able to map/cache the working set size for one process? 64 1024 128 512

asked Oct 12 in Operating System by Priyansh Singh (41 points) | 8 views

0 votes

1 answer

OS (ACE ACADEMY test series)

answered Oct 8 in Operating System by Saurabh Pandey (45 points) | 24 views

0 votes

1 answer

ace 2020 gate grand subject test series 2019-20
how to find the answer to the question below:

answered Oct 8 in Operating System by !KARAN (118 points) | 30 views

0 votes

1 answer

Ace grand chapter wise test OS 2019-20
what will be the answer of the below question

answered Oct 8 in Operating System by !KARAN (118 points) | 25 views

0 votes

0 answers

Ace grand subject Test Operating system
How to solve the below question? [closed]

asked Oct 7 in Operating System by Pratyush Priyam Kuan (72 points) | 14 views

0 votes

0 answers

ace academy test series OS

asked Oct 6 in Operating System by Priyansh Singh (41 points) | 19 views

0 votes

1 answer

#Self doubt #CPU_scheduling
"SJF and preemptive priority scheduling algorithm may lead to convoy effect." Above statement is true or false?

answered Oct 3 in Operating System by GAITONDE (1.2k points) | 13 views

0 votes

0 answers

What happens when V(S) is applied on a binary semaphore which is already initialized to 1?

asked Oct 2 in Operating System by commenter commenter (30 points) | 23 views

0 votes

0 answers

Peterson's Solution for mutual exclusion
L1:repeat L2: flag[i] = true; L3: turn = j; L4: while (flag[j]==True && turn==j) do no-op; L5: Enter critical section, perform actions, then L6: exit critical section L7: Flag[i] = false; L8: Perform ... false; L8: Perform other non-critical section actions. L9:Until false; Which of the Above two Implementations of Peterson's Algorithm are correct?

asked Oct 1 in Operating System by Sukhbir Singh (8 points) | 17 views

0 votes

1 answer

Operating System Made easy test series 2020
Consider the following statements: S1 : Translation look aside buffer necessarily be saved on a context switch between processes. S2: Program counter must be saved when context switch between processes. S3: System calls are usually invoked by using a software interrupt. Which of the above statements is/are correct?

answered Sep 29 in Operating System by GAITONDE (1.2k points) | 19 views

0 votes

1 answer

OS ACE Test Series Test 42 Q11 doubt on SSTF
First it moves from 70 to 68. At 68 it can go to either 50 (68-50=18) or 86 (86-68=18). So where should it should it go? If it goes to 68 (as given in their solution), total moves will be 310. But if it goes to 86 from 68 then total moves will be 250. What is the tie breaking rule here? I traced out both and wrote the minimum but got it wrong.

answered Sep 26 in Operating System by GAITONDE (1.2k points) | 24 views

+1 vote

1 answer

OS ACE Test Series Test 42 Q8 doubt on RR time quanta

answered Sep 26 in Operating System by GAITONDE (1.2k points) | 52 views

+1 vote

0 answers

OS ACE Test Series Test 42 Q15 doubt on SRTF
Is their solution correct? Why does P1 have to context switch at time 2 and 3? Can’t it simply run till completion (time 5)? My gantt chart is P1 | P2 | P3 so only 2 context switches (ignoring CS at begininning and end). Please help. Thank you.

asked Sep 26 in Operating System by DukeThunders (197 points) | 17 views

0 votes

0 answers

OS ACE Test Series Test 12 Q7
What is fastest way to solve this type of questions? Writing assembly code and checking for all possible ordering of statements is taking a lot of time. Is there any better approach?

asked Sep 26 in Operating System by DukeThunders (197 points) | 24 views

0 votes

1 answer

VANI TEST SERIES: OS
In case of threads which of the following are true ? I. Threads is a light weight process II. Threads can be executed independently III. A thread has its own context but shares code,data,files with other threads IV. Threads can not be executed in ... ll NONE Ans given is a, but why it is not b? Are threads independent? Threads are inter-dependent right, unlike processes?

answered Sep 25 in Operating System by GAITONDE (1.2k points) | 27 views

0 votes

0 answers

Self doubt about Memory access time
What is the difference between average memory access with TLB & a physically addressed cache. with TLB & a virtually addressed cache. what is their formula & how the overall translation happen in both cases with Hit & Miss ???

asked Sep 25 in Operating System by MRINMOY_HALDER (32 points) | 11 views

0 votes

0 answers

Page Table size: Self Doubt
How 2nd or 3rd level page table number of PTE depends on size of physical memory? Should it not depend on 1st level page table? Suppose we are given 24 bit Virtual Memory. Now, among this 24 bits 8 bits used for 1st level page table and 10 bit used ... and PTE=2B, how do we calculate 1st level, 2nd level page table size and size of addresses of each page table in bits?

asked Sep 25 in Operating System by srestha (318 points) | 25 views

0 votes

1 answer

Vani test series : Operating System
The System is in Deadlock state, this remark is→ True False Impossible to determine Unpredictable

answered Sep 25 in Operating System by Deepak Kumar 12 (55 points) | 21 views

0 votes

1 answer

Self Doubt: Progress and Deadlock
I have read that if Progress is satisfied then there can be no deadlock. Now consider these 2 programs below P1 P2 While(1) While(1) { { t1=true; t2= true; while(t2==true) ; while(t1==true) ; <c.s> <c.s> t1=false t2=false } } Aren’t they satisfying Progress as well as Deadlock at the same time?

answered Sep 24 in Operating System by Aditya Patel (46 points) | 24 views

0 votes

0 answers

ZEAL TEST SERIES: OPERATING SYSTEM
Suppose the following jobs are to be executed in a uni-processor system. Assume the overhead of context switching is one time unit. The average process turnaround time, the normalized turnaround time for process 2, and the processor efficiency using FCFS is, 12.8, 1.625, 83. ... 11.6, 3.75, 80.6% 18.6, 3.375, 71.4% Shouldn't the average turn around time be $11.8$?

asked Sep 21 in Operating System by GAITONDE (1.2k points) | 47 views

0 votes

1 answer

OS ACE Test Series Test 13 Q7 Indexing
I always face difficulties when solving this type of question so I am looking for a shortcut. I found a simple formula here, https://www.geeksforgeeks.org/gate-gate-cs-2019-question-51/. Using this formula for this problem, (4 KB/ 8 B ) ... also not able to use the formula for https://www.geeksforgeeks.org/gate-gate-cs-2004-question-49/ Please help. Thank you.

answered Sep 19 in Operating System by GAITONDE (1.2k points) | 17 views

0 votes

2 answers

livelock and deadlock
The condition: not (mutual exclusion and no preemption and circular wait and (hold and wait) )->no deadlock holds for deadlock only right?.And not for live lock.

answered Sep 18 in Operating System by Bikram (1.2k points) | 10 views

0 votes

4 answers

Is there any relation between starvation and bounded waiting?

answered Sep 18 in Operating System by Bikram (1.2k points) | 21 views

0 votes

2 answers

Minimum number of processes required to be present in the system to be in deadlock?

answered Sep 18 in Operating System by Bikram (1.2k points) | 10 views

To see more, click for all the questions in this category.

Recent questions and answers in Operating System

1,680 questions

1,088 answers

4,554 comments

89,591 users