Memory Management

Question

Consider a System Using Variable Partition with no Compaction

Free holes : 4K; 8K; 20K; 2K

Program size: 2K; 14K; 3K; 6K; 10K; 20K; 2K

Time for Execution:  4; 10; 2; 1; 4; 1; 8

Using Best Fit Allocation Policy and FCFS CPU Scheduling

Technique, Find the Time of Loading & Time of Completion of each program. The Burst Times are in Seconds.

Answer 1

Let's use the Best Fit Allocation policy and FCFS CPU scheduling technique to load and execute the programs. I'll go step by step:

1. Program size: 2K

   • Best Fit: Allocate in the 2K hole.
   • Time of Loading: 0 seconds (instantaneous)
   • Time of Completion: 4 seconds (execution time)

2. Program size: 14K

   • Best Fit: Allocate in the 20K hole (closest fit).
   • Time of Loading: 4 seconds (after the completion of the first program)
   • Time of Completion: 14 + 4 = 18 seconds

3. Program size: 3K

   • Best Fit: Allocate in the 4K hole.
   • Time of Loading: 18 seconds (after the completion of the second program)
   • Time of Completion: 18 + 2 = 20 seconds

4. Program size: 6K

   • Best Fit: Allocate in the 8K hole.
   • Time of Loading: 20 seconds (after the completion of the third program)
   • Time of Completion: 20 + 1 = 21 seconds

5. Program size: 10K

   • Best Fit: Allocate in the 20K hole (closest fit).
   • Time of Loading: 21 seconds (after the completion of the fourth program)
   • Time of Completion: 21 + 4 = 25 seconds

6. Program size: 20K

   • Best Fit: Allocate in the 20K hole (exact fit).
   • Time of Loading: 25 seconds (after the completion of the fifth program)
   • Time of Completion: 25 + 1 = 26 seconds

7. Program size: 2K

   • Best Fit: Allocate in the 4K hole.
   • Time of Loading: 26 seconds (after the completion of the sixth program)
   • Time of Completion: 26 + 8 = 34 seconds

So, the time of loading and time of completion for each program are as follows:

• Program 1: Load at 0 seconds, Complete at 4 seconds.
• Program 2: Load at 4 seconds, Complete at 18 seconds.
• Program 3: Load at 18 seconds, Complete at 20 seconds.
• Program 4: Load at 20 seconds, Complete at 21 seconds.
• Program 5: Load at 21 seconds, Complete at 25 seconds.
• Program 6: Load at 25 seconds, Complete at 26 seconds.
• Program 7: Load at 26 seconds, Complete at 34 seconds.