loop script command

[vagenrider]

hi guys,im running a script on my n9005 aosp kitkat and after 30-60 minutes seems that turn itself down or hanging..can anyone help me with some loop-repeat command to made this script non stop?

the script:
#!/system/bin/sh

echo mmc2 > /sys/class/leds/led:rgb_green/trigger;
echo mmc1 > /sys/class/leds/led:rgb_red/trigger;
echo mmc0 > /sys/class/leds/led:rgb_blue/trigger;