LED Heartbeat Trigger

modulename: ledtrig-heartbeat.ko

configname: CONFIG_LEDS_TRIGGER_HEARTBEAT

Linux Kernel Configuration
└─>Device Drivers
└─>LED Support
└─>LED Trigger support
└─>LED Heartbeat Trigger
In linux kernel since version 2.6.20 (release Date: 2007-02-04)  
This allows LEDs to be controlled by a CPU load average.
The flash frequency is a hyperbolic function of the 1-minute
load average.
If unsure, say Y.

source code: