CITS2002 Systems Programming  
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The 5-State Model of Process Execution

At this point, Stallings introduces his 5-state model:

This includes two new states:

  • New for newly created processes which haven't yet been admitted to the Ready queue for resourcing reasons;
  • Exit for terminated processes whose return result or resources may be required by other processes, e.g. for post-process accounting.

Each of these states, except for Running, is likely to 'hold' more than one process (i.e. there may be more than one process in one of these states).

If a queue of processes is not always ordered in a first-come-first-served (FCFS) manner, then a priority or scheduling mechanism is necessary.

 


CITS2002 Systems Programming, Lecture 8, p9, 20th August 2019.