ISRO CSE 2009
Q23.
Consider a set of 5 processes whose arrival time, CPU time needed and the priority are given below:\begin{array}{llll} \text { Process Priority } & \text { Arrival Time (in ms) } & \text { CPU Time Needed } & \text { Priority } \\ \text { P1 } & 0 & 10 & 5 \\ \text { P2 } & 0 & 5 & 2 \\ \text { P3 } & 2 & 3 & 1 \\ \text { P4 } & 5 & 20 & 4 \\ \text { P5 } & 10 & 2 & 3 \end{array}(smaller the number, higher the priority) If the CPU scheduling policy is priority scheduling without pre-emption, the average waiting time will beQ25.
The correct matching of the following pairs is\begin{array}{|l|l|l|l|} \hline \text{A.} & \text{Disk check} & \text{i.} & \text{Round robin} \\\hline \text{B.}& \text{Batch processing} & \text{ii.} & \text{Scan} \\\hline \text{C.} & \text{Time sharing} & \text{iii.} & \text{LIFO} \\\hline \text{D.} & \text{Stack operation} & \text{iv.} & \text{FIFO} \\\hline \end{array}Q26.
Consider three CPU-intensive processes, which require 10, 20 and 30 time units and arrive at times 0, 2 and 6, respectively. How many context switches are needed if the operating system implements a shortest remaining time first scheduling algorithm? Do not count the context switches at time zero and at the end.Q27.
Consider a system having "n" resources of same type. These resources are shared by 3 processes, A, B, C. These have peak demands of 3, 4, and 6 respectively. For what value of "n" deadlock won't occurQ28.
When a process is rolled back as a result of deadlock the difficulty which arises isQ30.
A data structure is required for storing a set of integers such that each of the following operations can be done in O(\log n) time, where n is the number of elements in the set. 1. Deletion of the smallest element 2. Insertion of an element if it is not already present in the set Which of the following data structures can be used for this purpose?