Process management in Operating System

Process concept- program under execution is called a process. Execution- if program is in execution-

1. It must reside in main memory.
2. should execute instruction on the processor.

Which instruction? – process instruction   Process have various attributes, states and operations.   Process ID (PID)- It is a unique identification no. which is assigned by operating system at the time of process creation. No two process have same ID. Program counter (PC)- It contains of address of next instruction to be executed. Process states (PS)- It contains the current state information of a process i.e in which state the process is currently residing. Priority- It is a para meter assigned by operating system at the time of process creation. e.g P1 has a priority of 2 P2 has a priority of 10 etc. General purpose registers (GPR)- A process using some registers for handling of data. List of open files (LOF)- What are the files opened by a process. List of open devices (LOD)- What are the devices by a process. All are the attributes of a process is called as context of the process. All are the attributes of a process are stated in Program Central Block (PCB).  ]]>