Most people don’t even know that running processes at at a different priority is an option. Many have never even heard of the nice command. In this article, I will discuss what the nice command can do for your processes.
Every process needs some time on the CPU regardless of its priority. Some get more time or run more often frequently because of their priority. Some are elevated in priority until their turn comes around.
A newly initiated process acquires the priority of it’s parent. For example, If you use the ls command after you log in, the ls process will inherit the priority of your shell. By using the nice command, you can lower the priority of a process. On some systems, the kernel will itself automatically boost the priority of a process when it has been waiting for a long time without being run.
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Also on same site: Neat crontab tricks .