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

View solution

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

View solution

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.

View solution

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

View solution

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 ?

View solution

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 ? 

View solution

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

View solution

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

View solution

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

View solution

Q. Translation Look-aside Buffer (TLB) is

View solution

Q. Simplest way of deadlock recovery is

View solution

Q. Possible thread states in Windows 2000 operating system include

View solution

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

View solution

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?

View solution

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

View solution

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?

View solution

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

View solution

Q. Which methods are utilized to control the access to an object in multi-threaded programming?

View solution

Q. Various storage devices used by an operating system can be arranged as follows in increasing order of accessing speed:

View solution

Q. How many disk blocks are required to keep list of free disk blocks in a 16 GB hard disk with 1 kB block size using linked list of free disk blocks? Assume that the disk block number is stored in 32 bits.

View solution