loadwatch - 1.0+1.1alpha1-8+b1 main

loadwatch forks a child process and only allows it to run when the
system load meets user-defined parameters. It allows you to specify
that a program should run only if the load is below a specified
point, and will stop it when that point is reached. When the load
falls below a second specified point, the program will be
continued. The user can also specify the system load sampling period.