Munin contributed plugins

#! /usr/bin/perl

########################################################################

# Copyright (c) 2012, Adrien Urban

# All rights reserved.

#

# Redistribution and use in source and binary forms, with or without

# modification, are permitted provided that the following conditions are

# met:

#

# 1. Redistributions of source code must retain the above copyright

#    notice, this list of conditions and the following disclaimer.

# 2. Redistributions in binary form must reproduce the above copyright

#    notice, this list of conditions and the following disclaimer in the

#    documentation and/or other materials provided with the

#    distribution.

#

# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS

# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT

# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR

# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT

# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,

# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT

# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,

# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY

# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT

# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE

# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

#

########################################################################

#                                                                      #

#    WARNING    WARNING    WARNING    WARNING    WARNING    WARNING    #

#                                                                      #

#       This plugin does not work properly with multiple master        #

#                                                                      #

########################################################################

#

# multigraph, supersampling, extended cpu information

#

# require: mpstat (to actually collect the data)

#

#

# ENV (default):

#  MUNIN_PLUGSTATE  - pid and cache files gets there

#

# ENV (user defined):

#  MUNIN_UPDATERATE - rate at which to update (default: 1s)

#  MUNIN_CACHEFLUSH_RATE - flush data every N batch (default: 1)

#  MUNIN_MPSTAT - binary to use as mpstat

#

#  increase cache flush rate if you have i/o performance issues

#  warning: increasing flushrate too much might cause partial write, and

#  loss of data. 0 to disable flush

#

#

# Parent graph: cpu usage per core/thread

# child graph(1): detailed cpu usage overall

# child graph(n): detailed cpu usage per thread

#

# Known bugs:

#

#   Multi-Master

#     If there are many masters, the data is only sent once. Each master will

#     only have part of the data.

#

#   Everlasting

#     The daemon is launched on first config/fetch. A touch of the pidfile is

#     done on every following config/fetch. The daemon should check if the

#     pidfile is recent (configurable) enough, and stop itself if not.

#

#   Graph Order

#     There is currently (2.0.6) noway to order childgraphs.

#

#   RRD file

#     The master currently (2.0.6) generate rrd file for aggregate values, and

#     complains that no data is provided for them (but the graph still works

#     fine)

#

#%# family=auto

#%# capabilities=autoconf

use strict;

use warnings;

my $plugin = $0;

$plugin =~ s/.*\///;

# quick failsafe

if (!defined $ENV{MUNIN_PLUGSTATE}) {

	die "This plugin should be run via munin. Try munin-run $plugin\n";

}

########################################################################

# If you want to change something, it's probably doable here

#

# order to display

my $fields_order = [

	'sys', 'usr', 'nice', 'idle', 'iowait', 'irq', 'soft', 'steal', 'guest',

];

# order is the order given by mpstat

my $fields_info = [

	{

		name => 'usr',

		label => 'usr',

		info => "%s time spent in normal programs and daemons",

	}, {

		name => 'nice',

		label => 'nice',

		info => "%s time spent in nice(1)d programs and daemons",

	}, {

		name => 'sys',

		label => 'sys',

		info => "%s time spent in kernel system activity",

	}, {

		name => 'iowait',

		label => 'iowait',

		info => "%s time spent waiting for blocking I/O operations",

	}, {

		name => 'irq',

		label => 'irq',

		info => "%s time spent handling interrupts",

	}, {

		name => 'soft',

		label => 'soft',

		info => "%s time spent handling software interrupts",

	}, {

		name => 'steal',

		label => 'steal',

		info => "%s time spent elsewhere (stolen from us)",

	}, {

		name => 'guest',

		label => 'guest',

		info => "%s time spent in a guest operating system",

	}, {

		name => 'idle',

		label => 'idle',

		info => "%s time spent idling (waiting to get something to do)",

	}

];

sub pidfile() { "$ENV{MUNIN_PLUGSTATE}/munin.$plugin.pid" }

sub cachefile() { "$ENV{MUNIN_PLUGSTATE}/munin.$plugin.cache" }

sub graph_name() { "cpu_extended_multi_1s" };

sub graph_title() { "CPU usage" };

sub graph_title_all() { "Overall CPU usage" };

sub graph_title_n($) { "CPU#" . (shift) . " usage" };

sub acquire_name() { "<$plugin> collecting information" }

########################################################################

# if you need to change something after that line, It should probably be

# changed to be configurable above it.

#

# mpstat sampling interval

my $update_rate = 1;

if (defined $ENV{MUNIN_UPDATERATE}) {

	if ($ENV{MUNIN_UPDATERATE} =~ /^[1-9][0-9]*$/) {

		$update_rate = int($ENV{MUNIN_UPDATERATE});

	} else {

		print STDERR "Invalid update_rate: $ENV{MUNIN_UPDATERATE}";

	}

}

my $flush_interval = 1;

if (defined $ENV{MUNIN_CACHEFLUSH_RATE}) {

	if ($ENV{MUNIN_CACHEFLUSH_RATE} =~ /^[0-9]+$/) {

		$update_rate = int($ENV{MUNIN_CACHEFLUSH_RATE});

	} else {

		print STDERR "Invalid flush rate: $ENV{MUNIN_CACHEFLUSH_RATE}";

	}

}

my $mpstat = "mpstat";

if (defined $ENV{MUNIN_MPSTAT}) {

	if (-f $ENV{MUNIN_MPSTAT}) {

		print STDERR "MUNIN_STAT: file not found: $ENV{MUNIN_MPSTAT}";

	} else {

		$mpstat = defined $ENV{MUNIN_MPSTAT};

	}

}

my $cpu_count_cache = undef;

sub cpu_count() {

	if (not defined $cpu_count_cache) {

               open MPSTAT, "$mpstat -P ALL |" or die "open mpstat|: $!\n";

               $cpu_count_cache = 0;

               while (<MPSTAT>) {

                       chomp;

                       my @field = split();

                       next unless ($field[1] && ($field[1] =~ /^([0-9]+)$/));

                       $cpu_count_cache ++;

               }

               close(MPSTAT);

	}

	return $cpu_count_cache;

}

sub is_running() {

	if (-f pidfile()) {

		my $pid = undef;

		if (open FILE, "<", pidfile()) {

			$pid = <FILE>;

			close FILE;

			chomp $pid;

		}

		if ($pid) {

			# does not exist ? kill it

			if (kill 0, $pid) {

				return 1;

			}

		}

 		unlink(pidfile());

	}

	return 0;

}

# FIXME: should also trap kill sigint and sigterm

# FIXME: check pidfile got touched recently

sub acquire() {

	$0 = acquire_name();

	$ARGV = [ '<daemon>' ];

	$0 = "<$plugin> collecting information";

	open PIDFILE, '>', pidfile() or die "open: @{[ pidfile() ]}: $!\n";

	print PIDFILE $$, "\n";

	close PIDFILE;

	open CACHE, ">>", cachefile() or die "open: @{[ cachefile() ]}: $!\n";

	open MPSTAT, "-|", "$mpstat -P ALL $update_rate" or

		die "open mpstat|: $!\n";

	my $flush_count = 0;

	while (<MPSTAT>) {

		chomp;

		my @field = split();

		if (!($field[1] =~ /^(all|[0-9]+)$/)) {

			next;

		}

		$field[0] = $field[1];

		$field[1] = time();

		print CACHE join(" ", @field), "\n";

		if ($flush_interval) {

			if ($flush_interval == ++$flush_count) {

				CACHE->flush();

				$flush_count = 0;

			}

		}

	}

	unlink(pidfile());

	unlink(cachefile());

}

sub run_daemon() {

	if (is_running()) {

		my $atime;

		my $mtime;

		$atime = $mtime = time;

		utime $atime, $mtime, pidfile();

	} else {

		if (0 == fork()) {

			close(STDIN);

			close(STDOUT);

			close(STDERR);

			open STDIN, "<", "/dev/null";

			open STDOUT, ">", "/dev/null";

			open STDERR, ">", "/dev/null";

			acquire();

			exit(0);

		}

	}

}

sub run_autoconf() {

	# in case we have specified args, check the file before that

	my $file = $mpstat;

	$file =~ s/ .*//;

	my $path = `which "$file"`;

	if ($path) {

		print "yes\n";

	} else {

		print "no\n";

	}

}

sub show_config($$$) {

	my $i = shift;

	my $name = shift;

	my $title = shift;

	my $graph_order = "graph_order";

	for my $field (@$fields_order) {

		$graph_order .= " $field";

	}

	print <<EOF;

multigraph @{[ graph_name() ]}.cpu$i

graph_title $title

graph_vlabel cpu use %

graph_scale no

update_rate 1

graph_data_size custom 1d, 10s for 1w, 1m for 1t, 5m for 1y

$graph_order

EOF

	for my $field (@$fields_info) {

		my $style = "STACK";

		if ($field->{name} eq $fields_order->[0]) {

			$style = "AREA";

		}

		print <<EOF;

$field->{name}.label $field->{label}

$field->{name}.draw $style

$field->{name}.info @{[ sprintf($field->{info}, $name) ]}

$field->{name}.min 0

$field->{name}.cdef $field->{name}

EOF

	}

}

sub run_config() {

	run_daemon();

	my $cpus = cpu_count();

	my $graph_order = "graph_order";

	my $sub_order = "order cpuall";

	for (my $i = 0; $i < $cpus; ++$i) {

		$graph_order .= " use$i=@{[ graph_name() ]}.cpu$i.idle";

		$sub_order .= " cpu$i";

	}

# none of those seems to have any effect

#domain_$sub_order

#node_$sub_order

#graph_$sub_order

#service_$sub_order

#category_$sub_order

#group_$sub_order

	print <<EOF;

multigraph @{[ graph_name() ]}

graph_category cpu

graph_title @{[ graph_title() ]}

graph_vlabel cpu use %

graph_scale no

graph_total All CPUs

update_rate 1

graph_data_size custom 1d, 10s for 1w, 1m for 1t, 5m for 1y

$graph_order

EOF

	my $style="AREA";

	for (my $i = 0; $i < $cpus; ++$i) {

		print <<EOF;

use$i.label CPU#$i

use$i.draw $style

use$i.cdef 100,use$i,-,${cpus},/

EOF

		$style = 'STACK';

	}

	# detailed sub graphs - 1 for all, and 1 per cpu

	show_config("all", "all CPU", graph_title_all());

	for (my $i = 0; $i < $cpus; ++$i) {

		show_config($i, "CPU$i", graph_title_n($i));

	}

}

sub fetch_showline($) {

	my $line = shift;

	my $n = 2;

	for my $field (@$fields_info) {

		print <<EOF;

$field->{name}.value $line->[1]:$line->[$n]

EOF

		++$n;

	}

}

sub run_fetch() {

	run_daemon();

	if (open CACHE, "+<", cachefile()) {

		my $cpus = {};

		while (<CACHE>) {

			chomp;

			my $field = [];

			@$field = split(/ /);

			if (not defined $cpus->{$field->[0]}) {

				$cpus->{$field->[0]} = [];

			}

			push @{$cpus->{$field->[0]}}, $field;

		}

		# finished reading ? truncate it right away

		truncate CACHE, 0;

		close CACHE;

		foreach my $cpu (keys %$cpus) {

			print <<EOF;

multigraph @{[ graph_name() ]}.cpu$cpu

EOF

			foreach my $line (@{$cpus->{$cpu}}) {

				fetch_showline($line);

			}

		}

	}

}

my $cmd = 'fetch';

if (defined $ARGV[0]) {

	$cmd = $ARGV[0];

}

if ('fetch' eq $cmd) {

	run_fetch();

} elsif ('config' eq $cmd) {

	run_config();

} elsif ('autoconf' eq $cmd) {

	run_autoconf();

} elsif ('daemon' eq $cmd) {

	run_daemon();

} else {

	print STDERR <<EOF;

$0: unrecognized command

Usage:

	$0 autoconf - check if we have everything we need

	$0 config - show plugin configuration

	$0 fetch - fetch latest data

	$0 daemon - launch daemon

EOF

	exit(1);

}

exit(0);

# for Munin Plugin Gallery

# graph_category cpu