Adjust value of OOM score to avoid process killed by kernel in case of Out of Memory

oom_score_adjust.sh

#!/bin/bash
# This script is used to disable OOM Killer for Ruby
# Process script will find the ruby process pid and change
# the OOM value to avoid being killed by kernel
# Author : Mansur Ul Hasan
# Email : [email protected]

# Function to find the PID
ProcessName='ruby'                      # Process Name
AppDir='/usr/local/script/oomadjust'    # Application path
PidFinder () {

        # Checking PID for process defined in {ProcessName} variable
        pgrep -f ruby |grep -v "grep\|pgrep" > $AppDir/conf/ruby.pid

        # Changing oom value to safe the process state in OOM situation
        for pid in `cat $AppDir/conf/ruby.pid`
        do
                ## Variable to check the process name with the help of $pid
                pidvalue=`cat /proc/$pid/status |grep Name |awk '{print $2}'`

                ## Checking if process is really the process we looking to optimize
                case $pidvalue in
                *ruby*)
                        # If process is valid value for oom_score_adj will be tune to lower value
                        echo "Process is valid $pidvalue"
                        echo -10 > /proc/$pid/oom_score_adj
                ;;
                *)
                        # if process is not valid event will not be logged.

                        echo $pidvalue
                        echo "Process is not valid ..."
                ;;
                esac
        done

}
# Main function caller
PidFinder