Linux daemon for alerting you if you're running out of memory

memory-alert.sh

#!/bin/bash

# Minimum available memory limit, MB
THRESHOLD=1024

# Check time interval, sec
INTERVAL=60

while :
do

    # For a more detailed message:
    # free=$(free -h | awk '/^Mem:/{print $4}')
    # shared=$(free -h | awk '/^Mem:/{print $5}')
    # bufcache=$(free -h | awk '/^Mem:/{print $6}')
    # available=$(free -h | awk '/^Mem:/{print $7}')
    # message="Free: $free\nShared: $shared\nBuffers/cached: $bufcache\nAvailable: $available\n\n~--\n\n$fortune"

    # MAKE SURE TO CHECK THIS AGAINST YOUR DISTRO'S VERSION OF `free`! Output formats may differ and you might not want `7`.
    available_mb=$(free -m | awk '/^Mem:/{print $7}')

    fortune=`fortune -a` # let's make it a little fun
    message="Only ${available_mb}MB available!\n·\n$fortune"

    if [ $available_mb -lt $THRESHOLD ]
        then
        notify-send -i face-surprise -u critical -t 20000 "Wait, holy shit, you're running out of memory" "$message"
    fi

    sleep $INTERVAL

done