SIGSTOP and SIGCONT are very useful as well. SIGSTOP is the equivalent of Ctrl-Z in a shell, but you can address it to any process. If you have a server being

SIGSTOP and SIGCONT are very useful as well. SIGSTOP is the equivalent of Ctrl-Z in a shell, but you can address it to any process. If you have a server being bogged down, you can stop the offending process temporarily. SIGCONT undoes SIGSTOP. The cpulimit tool does this in an automated way so that a process can be limited to use x% of CPU. Nice/renice doesn't keep your CPU from hitting 100% even with an idle priority process, which may be undesirable if it drains battery quickly or makes the cooling fan loud.