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Operating Systems | Time Aspects of Process

Important time parameters of process

  1. Arrival Time(AT)

    Entry time of process into ready queue.

  2. Burst Time(BT)

    Amount time spend for execution of process in CPU.

  3. Completion Time(CT)

    Finishing time of execution of the process

  4. Waiting Time(WT)

    Amount of time spend by process for waiting CPU after arrival and before completion.

  5. Turn Around Time(TAT)

    Time gap between arrival and completion time of a process.

  6. Response Time(RT)

    The range of time between initial scheduling and entry/arrival time of process.

  7. I/O Time

    The time spend for completion of input output request.

For an preemptive algorithm the the waiting time and burst time may be intermittent time slices(BT1/ WT1,BT2/ WT2...) of its over all burst time(BT)/waiting time(WT).

  • RT = tX - AT
  • CT - AT = BT + WT
  • WT = TAT - BT

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The execution of processes can be visualized …