Quickly change the niceness of running processes to manage CPU access and responsiveness. 30.11.2025 | reading time: 2 min Want to keep a server responsive while a heavy job runs? Use `renice` to change the niceness of a running process so it yields or grabs more CPU time, and see immediate effects without restarting the job. Hands-on Example Follow these steps to start a CPU hog, check its niceness, change it with `renice`, and verify the result: ```# start a CPU hog yes > /dev/null & PID=$! # before ps -p $PID -o pid,ni,cmd # sample output # PID NI CMD # 12345 0 yes # renice the process to be kinder renice +10 -p $PID # output # 12345: old priority 0, new priority 10 # after ps -p $PID -o pid,ni,cmd # PID NI CMD # 12345 10 yes``` Advanced Options `renice` accepts a numeric adjustment with -n and targets with -p for PID, -g for process group, or -u for user; values run from -20 (most favorable) to 19 (least favorable) and only root may set negative values so a process gets more CPU priority; remember that niceness is different from real-time scheduling and does not affect scheduling policies like SCHED_FIFO. When to Reach for Others Use `nice` to start processes with a chosen niceness, use `top` or `htop` to find PIDs and interactively renice, use `ionice` for I/O priority, and switch to `chrt` or cgroups when you need real-time scheduling or fine-grained resource control. Wrap-up and Next Steps Renicing is a fast, non-disruptive way to rebalance CPU attention on a running system; practice the example, explore `nice` and `chrt`, and consider deepening your Linux skills with certification preparation such as CompTIA Linux+ or LPIC-1 through intensive courses at bitsandbytes.academy. Join Bits & Bytes Academy First class LINUX exam preparation. processes utilities troubleshooting scripting
