For problems 1 and 2, a computer has the following four processes that have arrived in the ready queue in the sequence shown below. NOTE: There are no mandatory time outs required.
- Process 1 has a run time of 30 seconds, a priority of 1, and it will require 15 seconds of I/O after 10 seconds of execution.
- Process 2 has a run time of 20 seconds, a priority of 2, and it will require 10 seconds of I/O after 5 seconds of execution.
- Process 3 has a run time of 25 seconds and a priority of 2.
- Process 4 has a run time of 10 seconds and a priority of 1.
(HINT for problems 1 and 2: Review Module 6 section 2.1.2 for the definitions of these scheduling algorithms and Self-Assessment problems 1-4.)
1.
If the Round Robin Scheduling algorithm is used, which process completes second and why?
2.
If the Non-preemptive Priority Scheduling algorithm is used, which process completes first? At what time does it complete?
3.
Explain the trade-offs between contiguous, noncontiguous linked, and noncontiguous indexed file allocation. In particular, note the effect on sequential and random access methods.
4.
Using a variable-partitioned multiprogramming memory, which of the four holes shown below will be used to satisfy a 55 KB program requirement under the conditions of:
0-10 KB |
10-55 KB |
55-140 KB |
140-205 KB |
205-260 KB |
260-330 KB |
330-350 KB |
350-410 KB |
410-470 KB |
occupied |
Hole A |
Hole B |
Hole C |
Hole D |
___ First-fit___ Best-fit___ Worst-fit
(HINT: See Module 6 section 2.2.3 and Self Assessment problem 6.)