Get the total amount of memory used by a program running several threads

We should firstly get the pid of the parent process e.g.:

ps aux | grep mysqld

mysql     1842  1.1  7.2 2385476 748852 ?      Sl   Jun15.............

and then use ps to retrieve all of its threads and residential memory:

ps -p 1842 -L -o rss

and use awk to add up all of the output and convert to mb (or gb) e.g.:

ps -p 1842 -L -o rss | awk '{s+=$1/1024} END {print s}'

And to put it into a script we can do:

#!/bin/bash

application=$1

if [ -z "$1" ]; then

    echo "Please provide a process name in args!"

    exit

fi

pid=`ps aux | grep -v mysqld_safe | grep $application | grep -v grep | awk '{print $2}' | head -n1 | awk '{print $1;}'`

echo The total residential memory consumed by this application is `ps -p $pid -L -o rss | awk '{s+=$1/1024} END {print s}'`MB