Munin contributed plugins

#!/usr/bin/perl -w

# Sun JVM memory statistics.  Parses a verbose log of minor GC and

# tenured GC stats.

# To determine the totalheap value it looks for maxmem stats (from a

# tenured gc) in the last 5 minutes of the log file.  If there are no

# log lines in the last 5 minutes the value will be U(ndefined).

# Since the log lines are timestamped with seconds since the JVM

# started we look at the last line of the log to determine when "now"

# is for the JVM.  In a reasonably active JVM there will be several

# minor GCs a minute so the "now" approximation based on these log

# lines are close enough.

# Configuration (common with the other sun_jvm_* plugins in this family):

# [jvm_sun_*]

#    env.logfile /var/foo/java.log  (default: /var/log/app/jvm/gc.log)

#    env.graphtitle                 (default: "Sun Java")

# You need to configure your Sun JVM with these options:

# -verbose:gc

# -Xloggc:/var/log/app/jvm/gc.log

# -XX:+PrintGCTimeStamps

# -XX:+PrintGCDetails

# History:

# This plugin was developed by various people over some time - no logs

# of this has been found. - In 2006 significant contributions was

# financed by NRK (Norwegian Broadcasting Coproration) and performed

# by Nicolai Langfeldt of Linpro AS in Oslo, Norway.

# $Id: $

use strict;

use warnings;

use Fcntl qw(:seek);

# Full path to jvm log file

my $logfile = $ENV{logfile} || "/var/log/app/jvm/gc.log";

my $grtitle = $ENV{graphtitle} || "Sun Java";

# Title that appears on munin graph

my $title = "$grtitle memory usage";

# Extended information that appears below munin graph

my $info = "Write som info about this graph...";

sub analyze_record {

    # Match all interesting elements of a record and insert them

    # into a hash

    my $record = shift;

    my %elements;

    if ( $record =~

	 m/(\d+\.\d+).+?(\d+\.\d+).+?DefNew: (\d+).+?(\d+).+?(\d+).+?(\d+\.\d+).+?(\d+\.\d+): \[Tenured(\[U.+\])*: (\d+).+?(\d+).+?(\d+).+?(\d+\.\d+).+?(\d+).+?(\d+).+?(\d+).+?(\d+\.\d+).+/

	 ) {

	%elements = (

		     total_timestamp   => $1,

		     defnew_timestamp  => $2,

		     defnew_mem_from   => $3*1024,

		     defnew_mem_to     => $4*1024,

		     defnew_mem_max    => $5*1024,

		     defnew_time_used  => $6,

		     tenured_timestamp => $7,

		     tenured_mem_from  => $9*1024,

		     tenured_mem_to    => $10*1024,

		     tenured_mem_max   => $11*1024,

		     tenured_time_used => $12,

		     total_mem_from    => $13*1024,

		     total_mem_to      => $14*1024,

		     total_mem_max     => $15*1024,

		     total_time_used   => $16 );

    }

    return %elements;

}

my $record='';

# Print config information to munin server

if ( $ARGV[0] and $ARGV[0] eq "config" ) {

  print "graph_title $title\n";

  print "graph_vlabel Bytes Memory\n";

  print "graph_category virtualization\n";

  print "graph_args --lower-limit 0\n";

  print "graph_info Show heap memory usage of JVM\n";

  print "graph_order defnew_max tenured_max tenured_start tenured_end defnew_start defnew_end totalheap totalheapmax\n";

  print "defnew_max.label DefNew max\n";

  print "defnew_max.draw AREA\n";

  print "tenured_max.label Tenured max\n";

  print "tenured_max.draw STACK\n";

  print "tenured_max.info DefNew max and Tenured max are stacked to show the total heap memory usage\n";

  print "tenured_start.label Tenured start\n";

  print "tenured_start.info Tenured (long term) memory used at start of GC\n";

  print "tenured_end.label Tenured end\n";

  print "tenured_end.info Tenured (long term) memory used at end of GC\n";

  print "defnew_start.label DefNew start\n";

  print "defnew_start.info Short term memory used by objects at start of GC\n";

  print "defnew_end.label DefNew end\n";

  print "defnew_end.info Short term memory claimed by objects that survived the GC\n";

  print "totalheapmax.label Maximum total heap\n";

  print "totalheapmax.info Maximum used total heap last 5 minutes\n";

  print "totalheaptomax.label Total heap end\n";

  print "totalheaptomax.info Heapsize at maximum after GC\n";

  exit 0;

}

# Scan through the log file and keep the last instance of a

# Tenured record in $record.

my %last;

# We can't be sure that there is a totalmemto in the log.

my $totalmemto_atmax = 0;

my $totalmemfrom_max = 0;

open( FILE, "< $logfile" ) or die "Can't open $logfile: $!\n";

# We want to collect the highest total_mem_max in the last 5 minute period.

seek(FILE,-4096,SEEK_END);

my $now;

my $lastnow = 0;

while (<FILE>) {

    chomp;

    if (/:/) {

	($now,undef) = split(/:/,$_,2);

	$now = $lastnow unless $now;

    }

}

my $noolderthan = $now - 300;

# print "Latest time is: $now.  5 min ago is $noolderthan\n";

seek(FILE,0,SEEK_SET);

$lastnow = 0;

$now=0;

while (<FILE>) {

    chomp;

    if (/:/) {

	($now,undef) = split(/:/,$_,2);

	$now = $lastnow unless $now;

    }

    if (/.+Tenured.+/) {

	$record = $_;

    } elsif (/^:.+/) {

	$record .= $_;

    }

    if ($record =~ /Tenured.+secs\]$/) {

	%last = analyze_record($record);

#print "($now > $noolderthan and $last{total_mem_from} > $totalmemfrom_max)\n";

	if ($now > $noolderthan and $last{total_mem_from} > $totalmemfrom_max) {

	    $totalmemfrom_max = $last{total_mem_max};

	    $totalmemto_atmax = $last{total_mem_to};

#	    print "New larger at $now: $totalmemto_max\n";

	}

	$record = '';

    }

    $lastnow=$now;

}

close FILE;

$totalmemfrom_max=$totalmemto_atmax='U' if $totalmemfrom_max==0;

# Print the values to be represented in the munin graph

print "tenured_max.value  $last{total_mem_max}\n";

print "tenured_start.value $last{total_mem_from}\n";

print "tenured_end.value $last{total_mem_to}\n";

print "defnew_max.value $last{defnew_mem_max}\n";

print "defnew_start.value $last{defnew_mem_from}\n";

print "defnew_end.value $last{defnew_mem_to}\n";

print "totalheapmax.value $totalmemfrom_max\n";

print "totalheaptomax.value $totalmemto_atmax\n";