Munin contributed plugins

#!/usr/bin/env ruby

=begin

Munin Plugin for PGA memory components monitoring

Author: Wilfred Chau <openapp.developer@gmail.com>

Date: 2011-05-13

Version: 1.0

This program is free software; you can redistribute it and/or modify

it under the terms of the GNU General Public License version 2

as published by the Free Software Foundation.

This program is distributed in the hope that it will be useful,

but WITHOUT ANY WARRANTY; without even the implied warranty of

MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

GNU General Public License for more details.

You should have received a copy of the GNU General Public License along

with this program; if not, write to the Free Software Foundation, Inc.,

51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.

Prerequistes:

  1) env.ORACLE_HOME set in munin-node

  2) rubygems

  3) oci8 - DBI gem for connecting to Oracle

     * instruction of installing oci8 is available here:

       http://ruby-oci8.rubyforge.org/en/InstallBinaryPackage.html

Usage:

  1) copy this script to the munin install plugins directory (e.g. /usr/share/munin/plugins)

  2) chmod to allow executable to others

  3) create symbolic link in /etc/munin/plugins

           ln -s /usr/share/munin/plugins/oracle_<sid>_pga.rb /etc/munin/plugins/oracle_<sid>_pga.rb

           ** replace <sid> with your oralce sid

Parameters:

  autoconf

  config (required)

Configurable variables:

  orauser : oracle user who has select privilege to query v$pgastat view

  orapass : password for the oracle user

  dbport  : port used by the monitored instance (notice: numeric value)

  dbname  : database to be monitored

  dbhost  : host or ip address of db instance

#%# family=auto

#%# capabilities=autoconf

=end

require 'rubygems'

require 'oci8'

orauser  = 'munin'

orapass  = 'munin'

dbport   = 1522

dbname   = 'orcl'

dbhost   = 'localhost'

tnsname = "(DESCRIPTION =

            (ADDRESS = (PROTOCOL = TCP)(HOST = #{dbhost})(PORT = #{dbport}))

            (CONNECT_DATA = (SID = #{dbname})))"

def runQuery(name, query)

  rows = $conn.exec(query)

  puts "#{name}.value #{rows.fetch}"

  rows.close

end

#

# Queries

#

pga_target_query = "SELECT TO_CHAR(ROUND(decode(unit,'bytes',(value)/(1024*1024),value),2)) pga_target

                    from V$PGASTAT where name = 'aggregate PGA target parameter'"

pga_query = "SELECT TO_CHAR(ROUND(decode(unit,'bytes',(value)/(1024*1024),value),2)) pga

                     from V$PGASTAT where name = 'total PGA inuse'"

pga_components = { 'pga_target' => pga_target_query,

                   'pga_in_use' => pga_query }

#

# autoconf

#

case ARGV[0]

when 'autoconf'

  if tnsname.length > 1 && orauser.length > 1 && orapass.length > 1

    puts 'yes'

  else

    puts 'no'

    puts "Usage: #{__FILE__} autoconf|conf"

  end

  exit 0

#

# config definition

#

when 'config'

  puts 'graph_args --base 1024k -r --lower-limit 0'

  puts "graph_title Oracle PGA from #{dbname}"

  puts 'graph_category db'

  puts 'graph_info This graph shows the PGA memory usage (in MB)'

  puts 'graph_vlabel MB'

  puts 'graph_scale no'

  puts 'graph_period second'

  pga_components.keys.each do |p|

    puts "#{p}.label #{p}"

    puts "#{p}.info PGA: #{p}"

    puts "#{p}.type GAUGE"

    puts "#{p}.draw LINE1"

  end

  exit 0

end

$conn = OCI8.new(orauser, orapass, tnsname)

pga_components.each do |pc, query|

  runQuery(pc, query)

end

$conn.logoff