checkmemory.sh

#!/bin/bash
# This scripts pops up a notification in X if your RAM is occupied more
#   than a certain value (default: 90%).
# Memory is checked every 3 seconds, alerts pops up every 30 seconds.

checkmemory () {
        while
                sleep 3 
                TOTAL=`free -tw | grep Mem | tr -s ' ' | cut -d ' ' -f 2`
                USED=`free -tw | grep Mem | tr -s ' ' | cut -d ' ' -f 3`
                PERC=`echo 100* $USED / $TOTAL | bc`
                (( $PERC < $MAX ))
        do :; done
        BADPROCESS=`ps aux --sort -rss | head -2 | tail -1 | tr -s ' ' | rev | cut -d ' ' -f 1 | rev`
        xmessage "MEMORY ALERT - $PERC% occupied, mostly by $BADPROCESS" -center
}


if [ -v $1 ]
then
        MAX=90
else
        MAX=$1
fi

while
        checkmemory
        sleep 30
do :; done