First- fit
A. The first batch of jobs is loaded to the memory blocks. Job 1 searches for a block that is big enough. Searching can stop as soon as it can find a memory block that fits. Block 2 is the first memory block that fits Job1. Therefore, Job 1 is loaded to Block 2. Block 1 is the first one that fits Job 2. Block 3 first fits Job 3. Block 4 fits Job 4. Job 5 can not be loaded because Blocks 1 to 4 are already occupied and Block 5 has lesser memory than Job 5. Job 5 is placed in the waiting list.
B. Jobs 2 and 4 terminate and leave the memory block they occupy. Job 5 is loaded first. Block 1 is the first memory block that fits Job 5. Job 6 first fits in Block 4. Job 7 is placed in the waiting list for the same reason Job 5 was also placed in the waiting list.
C. Jobs 3 and 6 terminate. Job 7 is loaded to Block 3 where it first fits. Job 8 first fits on Block 4. Job 9 is placed in the waiting list.
D. Jobs 1, 5, and 7 terminate. Job 9 is loaded to Block 2 where it first fits. Job 10 is placed in the waiting list.
E. Job 8 terminates. Job 10 is loaded to Block 4 where it fits.
F. Jobs 9 and 10 continue processing.
G. Job 9 terminates. Job 10 is still processing.
H. Job 10 terminates.
Best- fit
A. Job 1 searches the entire list. It is loaded to the block which produces the smallest excess memory or leftover. In this case, Job 1 is loaded to Block 4, Job 2 to Block 5, Job 3 to Block 1, Job 4 to Block 3, and Job 5 to Block 2.
B. Jobs 4 and 2 terminate. Job 6 is loaded to Block 5, Job 7 to Block 3.
C. Jobs 3, 5, 7, and 6 terminate. Job 8 is loaded to Block 3, Job 9 to Block 2. Job 10 is placed in the waiting list because its memory exceeds the remaining free memory blocks.
D. Job 1 terminates. Job 10 is loaded to Block 4.
E. Job 8 terminates. Jobs 9 and 10 are still processing.
F. Job 9 terminates. Job 10 is still processing.
G. Job 10 terminates.
Worst- fit
A. In this case, the job searches the entire list and is loaded to the block which produces the largest leftover. Block 2 is the block where Job 1 produces the largest leftover. Job 2 to Block 4. Job 3 to Block 3. Job 4 to Block 1. Job 5 is placed in the waiting list.
B. Jobs 4 and 2 terminate. Job 5 searches the list of free memory block. Block 4 produces the largest leftover for Job 5. Job 6 is loaded to Block 1. Job 7 is placed in the waiting list.
C. Jobs 3 and 6 terminate. Job 7 is loaded to Block 3. Job 8 is placed in the waiting list.
D. Jobs 1, 5, and 7 terminate. Job 8 is loaded to Block 2, Job 9 to Block 4. Job 10 is placed in the waiting list.
E. Jobs 8 and 9 are still processing. Job 10 is still in the waiting list.
F. Job 9 terminates. Job 10 is still processing.
G. Job 10 is processing.
H. Job 10 terminates.
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