In Linux, there is no direct setting to limit the maximum CPU usage of a single process to 100%. CPU resources are usually allocated based on need and availability. However, there are some methods to regulate and control the CPU usage of processes:
1. `cpulimit`
2. `cgroups` (Control Groups):
3. `nice` and `renice`
4. Summary of process and CPU load on Linux!
1.) cpulimit
The cpulimit tool allows you to limit the CPU usage of a process.
- Installation
- On Debian-based systems:
sudo apt-get install cpulimit- On RHEL-based systems:
sudo yum install cpulimit
- Usage
To start a process and limit its CPU usage to 50%, you can use cpulimit like this:
cpulimit --exe <process name> --limit 50If the process is already running, you can use its PID:
cpulimit --pid <PID> --limit 50
2.) cgroups (Control Groups):
cgroups is a powerful feature of the Linux kernel that allows finer control over resource usage. It allows you to limit CPU usage and other resources to a group of processes.
- Using cgroups
1. Create a new cgroup
sudo mkdir /sys/fs/cgroup/cpu/mygroup
2. Set CPU allocation
- For example, to limit CPU time to 50%:
echo 50000 > /sys/fs/cgroup/cpu/mygroup/cpu.cfs_quota_us echo 100000 > /sys/fs/cgroup/cpu/mygroup/cpu.cfs_period_us
3. Add processes to cgroup
- For example:
echo <PID> > /sys/fs/cgroup/cpu/mygroup/cgroup.procs
3.) nice and renice
nice and renice affect the priority of processes, which can indirectly affect how much CPU a process can use, since lower priority processes can get less CPU time.
- Usage
- Start a new lower priority process:
nice -n 10 <command>
- Change the priority of a running process:
renice -n 10 -p <PID>
4.) Summary of process and CPU load on Linux!
Although you cannot directly limit the maximum CPU usage of a single process to 100%, cpulimit, cgroups and priority control by nice and renice provide flexible ways to control and optimize CPU usage. These tools allow you to better manage resource usage and minimize the impact on other processes on your system.
