Limit the CPU Usage of a Processhttp://limitcpu.sourceforge.net/
cpulimit is a simple program that attempts to limit the CPU usage of a process
(expressed in percentage, not in CPU time). This is useful to control batch
jobs when you don't want they eat too much CPU. It does not act on the nice
value or other scheduling priority details, but on the real CPU usage. Also, it
is able to adapt itself to the overall system load, dynamically and quickly.