CPU Scheduling
Q11.
For the real time operating system, which of the following is the most suitable scheduling scheme?Q12.
Consider the following processes, with the arrival time and the length of the CPU burst given in milli seconds.The scheduling algorithm used is preemptive shortest remaining-time first. The average turn around time of these processes is milliseconds.Q13.
Suppose two jobs, each of which needs 10 minutes of CPU time, start simultaneously. Assume 50% I/O wait time. How long will it take for both to complete, if they run sequentially?Q14.
In a lottery scheduler with 40 tickets, how we will distribute the tickets among 4 processes P1,P2,P3 and P4 such that each process gets 10%, 5%, 60% and 25% respectively?Q15.
Consider an arbitrary set of CPU-bound processes with unequal CPU burst lengths submitted at the same time to a computer system.Which one of the following process scheduling algorithms would minimize the average waiting time in the ready queue?Q16.
For the processes listed in the following table, which of the following scheduling schemes will give the lowest average turnaround time?Q17.
Which of the following strategy is employed for overcoming the priority inversion problem?Q18.
An operating system uses shortest remaining time first scheduling algorithm for pre-emptive scheduling of processes. Consider the following set of processes with their arrival times and CPU burst times (in milliseconds): The average waiting time (in milliseconds) of the processes is _________.Q19.
Consider a uniprocessor system executing three tasks T1, T2 and T3, each of which is composed of an infinite sequence of jobs (or instances) which arrive periodically at intervals of 3, 7 and 20 milliseconds, respectively. The priority of each task is the inverse of its period, and the available tasks are scheduled in order of priority, with the highest priority task scheduled first. Each instance of T1, T2 and T3 requires an execution time of 1, 2 and 4 milliseconds, respectively. Given that all tasks initially arrive at the beginning of the 1st millisecond and task preemptions are allowed, the first instance of T3 completes its execution at the end of _____________ milliseconds.Q20.
A particular parallel program computation requires 100 seconds when executed on a single CPU. If 20% of this computation is strictly sequential, then theoretically the best possible elapsed times for this program running on 2 CPUs and 4 CPUs respectively are