Question

1. What is internal and external fragmentation. Explain circumstances where one might be preferred over the other. [ 6pts]

2. Given the following: configuration with jobs arriving in order (Job A, B, C) and with blocks shown in order from low order memory to high order memory: [ 4 pts]

Job List:			Memory Block List:
Job Number	Memory Requested		Memory Block	Memory Block Size
Job A	60K		Block 1	10K
Job B	10K		Block 2	60K
Job C	250K		Block 3	100K

2. [4 pts]

Job List:			Memory Block List:
Job Number	Memory Requested		Memory Block	Memory Block Size
Job A	60K		Block 1	300K
Job B	10K		Block 2	60K
Job C	250K		Block 3	100K

1. For each table (a) and table (b) above

Use the first-fit algorithm to indicate which memory blocks are allocated to each of the arriving jobs.   

Use the best-fit algorithm to indicate which memory blocks are allocated to each of the arriving jobs.  

What are the differences you find in the first table and the second table for first fit and best fit algorithms. Explain your answer.

3. List one similarity and one difference between paged memory and demand paging memory allocation. Explain two (2) circumstances where one might be preferred over the other.  [ 6 pts]
4. What are the fundamental differences between paging scheme and segmented memory allocation? List both advantages and disadvantages of each neatly using tables [ 4 pts]

5. Which (3) tables are used by the memory manger to keep track of the segments in memory? Describe each table. [6 pts]

6. Why are segmentation problem like, compaction and external fragmentation removed in the combined segmented/demand paged memory allocation? [2 pts]

7.   Given the following Segment Map Tables for two jobs below: [8 pts]

SMT for Job 1 Segment Number	Memory Location
0	4096
1	6144
2	9216
3	2048
4	7168

SMT for Job 2 Segment Number	Memory Location
0	2048
1	6144
2	9216

a. Which segments, if any, are shared between the two jobs?

b.   If the segment now located at 7168 is swapped out and later reloaded at 8192, and the segment now at 2048 is swapped out and reloaded at 1024, what would the new segment tables look like? [Draw the new tables]

8. Give an example of each, first-in-first out (FIFO) and least-recently–used (LRU) policy. [5 pts]
9. Show how much virtual memory and physical memory is in use by the Windows operating system.  Use the Resource monitor manager or the CMD command.  <<Show screenshot>> [Hint : You can research it on the web. One such web page is here]  [ 5 pts]

https://www.techrepublic.com/article/how-to-use-windows-10s-resource-monitor-to-track-memory-usage/

Answer 1

7 )

a ) The segments shared between two jobs :

• If we take a look at the segment map table for job1 and segment map tool table for job 2 ,it is very clear that three segments are shared between them
• The segment at memory location 2048,6144 and 9216 are shared by two segment tables.

Therefore, the segments shared by SMT for job1 and SMT by job2 are at the memory locations.

2048,6144 and 9216.

b) Swapping out the segments and reloading it in other locations and then

displaying new SMT for job1 and job2:

The following data consists of the segments which are swapped out and later reloaded in different memory

locations.

The segment located at 7168 is swapped out of the memory and then the segment is reloaded in memory

location 8192.

The segment located at 2048 is swapped out of the memory and then the segment is reloaded in memory location 1024.

The following table consists of the new Segment Map Table for job1 and job2:

segment map table for job1:

Segment Number	Memory Location
0	4096
1	6144
2	9216
3	1024
4	8192

segment map table for job2:

Segment Number	Memory Location
0	1024
1	6144
2	9216

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ANSWERED AS PER MY KNOWLEDGE

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