Q. If the disk head is located initially at 32, find the number of disk moves required with FCFS if the disk queue of I/O blocks requests are 98, 37, 14, 124, 65, 67.

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Q. Given memory partitions of 100 K, 500 K, 200 K, 300 K and 600 K (in order) and processes of 212 K, 417 K, 112 K, and 426 K (in order), using the first-fit algorithm, in which partition would the process requiring 426 K be placed ?

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Q. The problem of indefinite blockage of low-priority jobs in general priority scheduling algorithm can be solved using :

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Q. Which of the following memory allocation scheme suffers from external fragmentation ?

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Q. Match the following :
List – I                                              List – II
a. Critical region                            1. Hoares Monitor
b. Wait/signal                                 2. Mutual exclusion
c. Working set                               3. Principal of locality
d. Dead lock                                  4. Circular wait

Codes : a b c d

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Q. Which of the following features will characterize an OS as multiprogrammed OS ?

(a) More than one program may be loaded into main memory at the same time.
(b) If a program waits for certain event another program is immediately scheduled.
(c) If the execution of a program terminates, another program is immediately scheduled.

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Q. A thread is a light weight process. In the above statement, weight refers to

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Q. Consider a system having m resources of the same type. These resources are shared by 3 processes A, B and C which have peak demands of 3, 4 and 6 respectively. For what value of m deadlock will not occur ?

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Q. Consider n processes sharing the CPU in round robin fashion. Assuming that each process switch takes s seconds. What must be the quantum size q such that the overhead resulting from process switching is minimized but, at the same time each process is guaranteed to get its turn at the CPU at least every t seconds ? 

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Q. The virtual address generated by a CPU is 32 bits. The Translation Look-aside Buffer (TLB) can hold total 64 page table entries and  4-way set associative (i.e.with4-cache lines in the set). The page Sill' is 4 KB. The minimum size of TLB tag is

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Q. Consider a disk queue with request for input/output to block on cylinders

98,183,37,122,14, 124, 65, 67 in that order

Assume that disk head is  initially positioned at cylinder 53  and moving towards cylinder number 0. The total number of head movements using Shortest Seek lime First (SSTF) and SCAN algorithms are respectively

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Q. How much space will be required to store the bit map of a 1.3 GB disk with 512 bytes block size

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Q. Translation Look-aside Buffer (TLB) is

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Q. Simplest way of deadlock recovery is

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Q. Possible thread states in Windows 2000 operating system include

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Q. Which of the following conditions does not hold good for a solution to a critical section problem?

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Q. In a demand paging memory system, page table is held in registers. The time taken to service a page fault is 8 m.sec. If an empty frame is available or if the replaced page is not modified, and it takes 20 m.sec., if the replaced page is modified. What is the average access time to service a page fault assuming that the page to be replaced is modified 70% of the time?

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Q. The directory can be viewed as _______ that translates filenames into their directory entries.

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Q. Consider the following justifications for commonly using the two-level CPU scheduling :

I. It is used when memory is too small to hold all the ready processes.

II. Because its performance is same as that of the FIFO.

III. Because it facilitates putting some set of processes into memory and a choice is made from that.

IV. Because it does not allow to adjust the set of in-core processes.

Which of the following is true?

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Q. For the implementation of a paging scheme, suppose the average process size be x bytes, the page size be y bytes, and each page entry requires z bytes. The optimum page size that minimizes the total overhead due to the page table and the internal fragmentation loss is given by

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