#4- VARIOUS PROCESS STATES-

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  •  New(create): In this step, the process is about to be created but not yet created. It's the program that is present in secondary memory that will be picked up by OS to create the process.
  •  Run: the process is chosen from the ready queue by the CPU for execution and the instruction within the process are executed by any one of the available CPU cores.
  • Ready: New-> ready to run. after the creation of a process , the process enters the ready state that is the process is loaded into the main memory. the process here is ready to run and is waiting to get the CPU time for its execution .
  • Blocked or Wait: whenever the process request access to I/O or needs input form the user or need access to a critical region the process continues to wait in the main memory and does require CPU. once the I/O operation is completed the process goes to the ready state.
  • Terminated or Completed: process is killed as well as PCB is detected. the resources allocated to the process will be released or deallocated.
  •  Suspended Ready: Process that was initially in the ready state but was swapped out of main memory (refer to Virtual memory ) and placed onto external storage by the scheduler is said to be in suspend ready state.  
  • Suspend wait or suspend blocked: Similar to suspend ready but uses the process which was performing I/O (input/output) operation and lack of main memory caused them to move to secondary memory .when work is finished it may go to suspend ready.
  •  CPU and I/O Bound Processes: if the process is intensive in terms of CPU operations, then it is called CPU bound process. Similarly, if the process is intensive in terms of I/O operations then it is called I/O bound process.


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