A system has an 1024KB block of memory available as shown below. Processes Pl an

Question

A system has an 1024KB block of memory available as shown below. Processes Pl and P2 have already been in memory when processes P3(75KB), P4(210KB), P5(120KB), P6(55KB) and P7(119KB) arrive in this P3, P4, P5, P6 and P7 arrive. How these processes placement algorithms: (i) first fit, (ii) next fit, (ii) best fit, (iv) worst fit. If a process cannot be placed into memory, label it as out of memory order. Assume that P2 is the last process loaded into memory before would be placed in memory by the following Process Memory Area Size 1-100 101-160 161-400 401-530 531-700 701-780 781-905 906-1024 100 60 240 130 170 80 125 119 P1 P2 ext fit First fit Process Memory Area Size KB Process Memory Area Size KB Worst fit rocess Memory Area Size[KB Process Memory Area Size KB

Explanation / Answer

Process Memory Area Size(KB)
P1      1-100      100
         101-160     60
         161-400     240
         401-530     130
P2     531-700     170
         701-780      80
         781-905     125
         906-1024    119
First fit is as follows: (The first free block capable of accomodating the requirement is selected
Process Memory Area Size(KB)    (P4 can not be allocated)
P1      1-100      100
P6     101-155     55      (P6 came and get allocated to 60 size block.because of which two partitions of size 55 and 5 got created)
         156- 160    5
P3     161-235     75      (P3 came and get allocated to 240 size block.because of which two partitions of size 75 and 165 got created)
P5     236-355     120     (P5 came and get allocated to 165 size block.because of which two partitions of size 120 and 45 got created)
         356-400     45
P7     401-519     119     (P7 came and get allocated to 130 size block.because of which two partitions of size 119 and 11 got created)
         520-530     11
P2     531-700     170
         701-780      80
         781-905     125
         906-1024    119
Next fit is as follows: Similar to first fit but search starts from where the last selection ended.
Process Memory Area Size(KB)   (P4 can not be allocated)
P1      1-100      100
         101-160     60
P3     161-235     75         (P3 came and get allocated to 240 size block.because of which two partitions of size 75 and 165 got created)
P5     236-355     120        (P5 came and get allocated to 165 size block.because of which two partitions of size 120 and 45 got created)
         356-400     45
P6     401-455     55         (P6 came and get allocated to 130 size block.because of which two partitions of size 55 and 75 got created)
         456-530     75
P2     531-700     170
      701-780      80       
P7     781-899     119        (P7 came and get allocated to 125 size block.because of which two partitions of size 119 and 6 got created)
         900-905      6
         906-1024    119

Best fit is as follows: All the options are considered and the smallest block that
can hold is selected
Process Memory Area Size(KB)  
P1      1-100      100
P6     101-155     55      (P6 came and get allocated to 60 size block because of which two partitions of size 55 and 5 got created )
       156- 160     5
P4     161-400     210     (P4 came and get allocated to 240 size block because of which two partitions of size 210 and 30 got created )
       371-400     30
       401-530     130
P2     531-700     170
P3     701-775      75      (P3 came and get allocated to 80 size block because of which two partitions of size 75 and 5 got created )
       776-780      5
P5     781-900     120      (P5 came and get allocated to 125 size block.because of which two partitions of size 120 and 5 got created ) )
       901-905      5
P7     906-1024    119      (P7 came and get allocated to 119 size block.)

Worst fit is as follows: All the options are considered and the biggest block that
can hold is selected. It is opposite of best fit.
Process Memory Area Size(KB)     (P4 can not be allocated)
P1      1-100      100
         101-160     60
P3     161-235     75         (P3 came and get allocated to 240 size block because of which two partitions of size 75 and 165 got created )
P5     236-355     120        (P5 came and get allocated to 165 size block because of which two partitions of size 120 and 45 got created )
       356-400     45
P6     401-455     55         (P6 came and get allocated to 130 size block because of which two partitions of size 55 and 75 got created )
         456-530     75
P2     531-700     170      
         701-780      80
P7     781-899     119       (P7 came and get allocated to 125 size block because of which two partitions of size 119 and 6 got created )
         900-905      6
         906-1024    119

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.