3.1 Review question: synchronization  (Page 3/4)

         P4                   -- -- -- -- -- 

         P5                          -- -- -- ----

FB q=2^i P1 -- ----

         P2    --      ---- ----

         P3          --    --     

         P4                      ------ ----

         P5                            --    --------

For feedback queueing with a quantum of 1, I assume that when a process is taken off the processor and placed in a lower priorityqueue, it is not eligible to go right back onto the processor. It must wait another quantum. For feedback queueing with a quantum of 2i, I assume that anewly arriving process can't preempt the current process until it is done with its quantum. This is different from the book's assumption and thereforedifferent from Figure 9.5 in the book.

Here are the metrics:

               1     2     3     4     5

       Ta      0     1     3     9    12

       Ts      3     5     2     5     5

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FCFS   Tf      3     8    10    15    20

       Tq      3     7     7    6     8    6.20

     Tq/Ts   1.00 1.40 3.50 1.20 1.60   1.74

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RR q=1 Tf      6    11     8    18    20

       Tq      6    10     5     9     8    7.60

     Tq/Ts   2.00 2.00 2.50 1.80 1.60   1.98

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RR q=4 Tf      3    10     9    19    20

       Tq      3     9     6    10     8    7.20

     Tq/Ts   1.00 1.80 3.00 2.00 1.60   1.88

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SPN    Tf      3    10     5    15    20

       Tq      3     9     2     6     8   5.60

     Tq/Ts   1.00 1.80 1.00 1.20 1.60   1.32

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SRT    Tf      3    10     5    15    20

       Tq      3     9     2     6     8    5.60

     Tq/Ts   1.00 1.80 1.00 1.20 1.60   1.32

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HRRN   Tf      3    10     5    15    20

       Tq      3     7     7     6     8    6.20

     Tq/Ts   1.00 1.40 3.50 1.20 1.60   1.74

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FB q=1 Tf      7    11     6    18    20

       Tq      7    10     3     9     8    7.40

     Tq/Ts   2.33 2.00 1.50 1.80 1.60   1.85

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FB q=1 Tf      4    10     8    16    20

       Tq      4     9     5     7     8    7.00

     Tq/Ts   1.33 1.80 2.50 1.40 1.60   1.81

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Assume the following burst-time pattern for a process: 6,4,6,4,13,13,13, and assume that the initial guess is 10.

Five batch jobs, a through e, arrive at a computer center at essentially the same time. they have an estimated running time of 15, 9, 3, 6,And 12 minutes, respectively. their (externally defined) priorities are 6, 3, 7, 9, and 4 respectively, with a lower value corresponding to a higher priority.For each of the following scheduling algorithms, determine the turnaround time for each process and the average turnaround time for all jobs. ignore processSwitching overhead. explain how you arrived at your answers. in the last three cases, assume that only one job at a time runs until it finishes and that allJobs are completely processor bound.

Process    Running Time      Priority