In operating systems, aging refers to a technique used in scheduling algorithms, particularly in process scheduling. It is a method employed to prevent a situation called "starvation" or "priority inversion."
In process scheduling, each process is assigned a priority level that determines its order of execution. The priority can be adjusted dynamically based on various factors such as process behaviour, resource requirements, or system policies. However, without proper management, lower-priority processes may suffer from starvation, where they are constantly delayed or prevented from executing due to higher-priority processes continuously occupying system resources.
To address this issue, aging is introduced. Aging involves gradually increasing the priority of a process over time if it remains in a lower-priority state for an extended period. As a result, processes that have been waiting for a long time receive a boost in priority, ensuring they eventually get a chance to execute and prevent indefinite delays.
The aging technique works by periodically incrementing the priority level of processes that have not received CPU time for a certain duration. By gradually elevating their priority, aging ensures that lower-priority processes have an opportunity to run and avoid being starved indefinitely by higher-priority processes.
Aging helps maintain fairness and prevent resource starvation in the system. It ensures that processes with lower priorities are not constantly neglected and are given a chance to execute, promoting better overall system performance and responsiveness.
