.. _hw_schedulers:

Homework - Analysis of Schedulers
===============================================

#.  Consider the following table showing arrival times and service times for
    a set of static processes.  Draw a chart illustrating their execution and
    compute the average turnaround time and average response time using the 
    following scheduling algorithms. (See :ref:`metrics`)

    a) :ref:`fcfs`

    b) :ref:`sjn`

    c) :ref:`rr` with time quantum = 10


    =======  =============  =============
    Process  Arrival Time   Service Time
    =======  =============  =============
        A       0               21
        B       5               9
        C       23              30
        D       26              10
        E       30              15
    =======  =============  =============

#.  

    Now consider a :ref:`priority_queues` with 3 queues.  The scheduler uses
    time quantum of 5 15 20 for the three queues.  The following table
    shows processes that will block for I/O a few times before completing.
    The table shows the arrival times, service times and following blocked
    times for a set of processes.  Draw a chart illustrating their execution
    and compute the average turnaround time, average response time and
    average waiting time.  (See :ref:`metrics`)

    =======  =============  ============= ==============
    Process  Arrival Time   Service Time   Blocked Time
    =======  =============  ============= ==============
        A       0               12          69

                                10          70

                                8

        B       5               9           53

                                4           48

                                3           69

                                8

        C       23              30          70

                                25          65

                                20

        D       26              10          77

                                15          89

                                11

        E       30              12          55

                                18          60

                                3           65

                                3           56

                                4           47

                                6

    =======  =============  ============= ==============