Munin contributed plugins

#!/bin/sh

#

# Plugin for monitor JVM activity - Heap Usage -

#

# Usage:

#

#       Symlink into /etc/munin/plugins/ and add the monitored

#	alias name like :

#

#       ln -s /usr/share/munin/plugins/jstat__heap \

#	  /etc/munin/plugins/jstat_<jvm alias>_heap

#       This should, however, be given through autoconf and suggest.

#

# Requirements:

#

#	You need to execute your Java program under jsvc provided by

#	  http://jakarta.apache.org/commons/daemon/

#	which enables you to run your Java program with specified

#	pid file with -pidfile option.

#       A Brief setup documentation is also available at

#         http://tomcat.apache.org/tomcat-5.5-doc/setup.html

#

# Target:

#

#       Target Java Virtual Machine to monitor are:

#         Sun JDK 5.0 (http://java.sun.com/javase/)

#         Sun JDK 8.0 (http://java.sun.com/javase/)

#         OpenJDK 1.7 .. 11 (https://openjdk.java.net/)

#         BEA JRockit 5.0 (http://dev2dev.bea.com/jrockit/)

#

# Parameters:

#

#       config   (required)

#

# Config variables:

#

#       pidfilepath  - Which file path use. Defaults to '/var/run/jsvc.pid'

#       javahome     - override automatic detection of JRE directory

#       graphtitle   - Title of the graph (defaults to PID file location)

#

default_java_home=/usr/lib/jvm/default-java

[ -e "$default_java_home" ] || default_java_home=/usr/local/java/jdk

pidfilepath=${pidfilepath:-/var/run/jsvc.pid}

graphtitle=${graphtitle:-$pidfilepath}

JAVA_HOME=${javahome:-$default_java_home}

export JAVA_HOME

get_jdk_type() {

    local version

    if "${JAVA_HOME}/bin/java" -version 2>&1 | grep -qi 'jrockit'; then

        echo "bea"

    else

        echo "sun"

  fi

}

print_config() {

    echo "graph_title Heap Usage $graphtitle"

    echo "graph_args --base 1024 -l 0"

    echo "graph_vlabel Heap Usage(Bytes)"

    echo "graph_info Heap Usage"

    echo "graph_category virtualization"

    if [ "${JDK_TYPE}" = "bea" ]; then

        echo "NurserySize.label NurserySize"

        echo "HeapSize.label HeapSize"

        echo "UsedHeapSize.label UsedHeapSize"

        echo "NurserySize.draw AREA"

        echo "HeapSize.draw STACK"

        echo "UsedHeapSize.draw STACK"

    else

        echo "Eden_Used.label Eden_Used"

        echo "Eden_Free.label Eden_Free"

        echo "Survivor0_Used.label Survivor0_Used"

        echo "Survivor0_Free.label Survivor0_Free"

        echo "Survivor1_Used.label Survivor1_Used"

        echo "Survivor1_Free.label Survivor1_Free"

        echo "Old_Used.label Old_Used"

        echo "Old_Free.label Old_Free"

        echo "Permanent_Used.label Permanent_Used"

        echo "Permanent_Free.label Permanent_Free"

        echo "Eden_Used.draw AREA"

        echo "Eden_Free.draw STACK"

        echo "Survivor0_Used.draw STACK"

        echo "Survivor0_Free.draw STACK"

        echo "Survivor1_Used.draw STACK"

        echo "Survivor1_Free.draw STACK"

        echo "Old_Used.draw STACK"

        echo "Old_Free.draw STACK"

        echo "Permanent_Used.draw STACK"

        echo "Permanent_Free.draw STACK"

    fi

}

print_stats() {

    local pid_num="$1"

    local awk_script

    if [ "${JDK_TYPE}" = "bea" ]; then

        # shellcheck disable=SC2016

        awk_script='{

            HeapSize = $1;

            NurserySize = $2;

            UsedHeapSize = $3;

            print "NurserySize.value " NurserySize * 1024;

            print "HeapSize.value " HeapSize * 1024;

            print "UsedHeapSize.value " UsedHeapSize * 1024; }'

    else

        # List & Order of columns of jstat changes with java versions

        # idx["YGC"] is index of YGC column in output (i.e. 13)

        # $idx["YGC"] then accesses the value at this position (taken from 2nd line of the output)

        # shellcheck disable=SC2016

        awk_script='

	    NR==1 { 

                for (i=1;i<=NF;i++) idx[$i]=i

            }

            NR==2 {

                S0F = $idx["S0C"] - $idx["S0U"];

                S1F = $idx["S1C"] - $idx["S1U"];

                EF  = $idx["EC"]  - $idx["EU"];

                OF  = $idx["OC"]  - $idx["OU"];

                MF  = $idx["MC"]  - $idx["MU"];

                print "Eden_Used.value " $idx["EU"] * 1024;

                print "Eden_Free.value " EF * 1024;

                print "Survivor0_Used.value " $idx["S0U"] * 1024;

                print "Survivor0_Free.value " S0F * 1024;

                print "Survivor1_Used.value " $idx["S1U"] * 1024;

                print "Survivor1_Free.value " S1F * 1024;

                print "Old_Used.value " $idx["OU"] * 1024;

                print "Old_Free.value " OF * 1024;

                print "Permanent_Used.value " $idx["MU"] * 1024;

                print "Permanent_Free.value " MF * 1024;

            }'

    fi

    "${JAVA_HOME}/bin/jstat" -gc "$pid_num" | awk "$awk_script"

}

#

# autoconf

#

if [ "$1" = "autoconf" ]; then

  if [ ! -x "${JAVA_HOME}/bin/jstat" ]; then

    echo "no (No jstat found in ${JAVA_HOME}/bin)"

  elif [ ! -f "$pidfilepath" ]; then

    echo "no (missing file $pidfilepath)"

  elif [ ! -r "$pidfilepath" ]; then

    echo "no (cannot read $pidfilepath)"

  else

    echo "yes"

  fi

  exit 0

fi

JDK_TYPE=$(get_jdk_type)

if [ "$1" = "config" ]; then

    print_config

fi

print_stats "$(cat "$pidfilepath")"