Process States and Transitions

Processes in an operating system transition through various states throughout their lifecycle, representing different stages of execution and resource availability. The fundamental process states include: New (process being created), Ready (process waiting to be assigned to CPU), Running (instructions being executed on CPU), Waiting (process waiting for some event such as I/O completion), and Terminated (process has finished execution). State transitions occur based on specific events: a new process moves to Ready when initialization completes; a Ready process moves to Running when scheduled by the OS; a Running process moves to Waiting when it requests an operation that requires waiting (like I/O); a Waiting process moves to Ready when the event it was waiting for occurs; a Running process moves to Ready when its time quantum expires or a higher priority process becomes ready; and a Running process moves to Terminated when it completes execution or is explicitly killed. Some systems include additional states like Suspended (process swapped out of memory) or Zombie (process terminated but still has an entry in process table). Understanding process states and transitions is essential for system designers and developers to create efficient scheduling algorithms, debug process-related issues, and optimize system performance by minimizing unnecessary state transitions and associated overhead.