Linux has an option of Frequency Scaling which lets us adjust the maximum CPU usage of the whole system instantaneously. But, sometimes we might like to selectively apply CPU resources and speeds to applications.

This is possible on Linux with CPU Limit. CPU Limit lets us limit the CPU usage of a particular application or a process by it’s PID ( Process ID )on a Linux system according to a percentage, the current usage being 100%.

Not only this, CPU Limit can automatically adjust itself according to the overall system load, so we can always use CPU limit safely, without the fear of causing any unbalanced activity.

Currently CPU Limit can only be used from the command line. For a detailed overview on how to use CPU Limit, you can check out this page ^[1].

CPU Limit has a minimum system requirement of the Linux Kernel 2.2. One notable fact here is that, if you have multi-CPU system, your maximum CPU frequency limit is not 100 % but n times 100, where n is the number of CPUs. Another limitation is that CPU Limit can only allow you to under-clock a process, but not over-clock it. But still, it is the first application of it’s kind for Linux.

To get CPU Limit, go to the SourceForge page on CPU Limit here : Download CPU Limit ^[2]