Munin contributed plugins

#!/usr/bin/perl -w

=head CONFIGURATION

    Based on Redis module code v0.08 2009/from http://svn.rot13.org/index.cgi/Redis

    Installation process:

    1. Download the plugin to your plugins directory (e.g. /usr/share/munin/plugins)

    2. Symlink it to your configuration directory (e.g. ln -s /usr/share/munin/plugins/redis /etc/munin/plugins/redis)

    3. Edit plugin-conf.d/munin-node with the options to connect to your redis instances (see below for an example)

    4. Restart munin-node service

    Example config

    [redis]

    env.host1 127.0.0.1

    env.port1 6379

    env.password1 password

    env.title_prefix1 redis-1

    env.host2 /run/redis.sock

    env.title_prefix2 redis-2

    Each host should be specified with at least a host or unixsocket variable suffixed with

    a number, the first being 1, the second being 2 etc. They must be in sequence.

    Other options are:

    * port - the redis port to connect to

    * password - the password to use with the AUTH command

    * title_prefix - a prefix to put before the title of the graph, this is strongly recommended for multiple instances

    Graphs:

    This generates multigraphs for:

    * Connected clients

    * Key Hit vs Miss ratio

    * Keys per second, hits/misses/expirations/evictions

    * Replication backlog

    * Replication lag

    * Request per second

    * Total number of keys and keys with expires

    * Used memory

=head COPYRIGHT

    Copyright (C) 2020 Rowan Wookey <https://www.rwky.net/>

    Copyright (C) 2009 Gleb Voronich <http://stanly.net.ua/>

=head LICENSE

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

    modify it under the terms of the GNU General Public License

    as published by the Free Software Foundation; version 2 dated June,

    1991.

    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., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.

=head MAGIC MARKERS

    #%# family=auto

    #%# capabilities=autoconf

=cut

use strict;

use IO::Socket::INET;

use IO::Socket::UNIX;

my %INSTANCES;

my $HOST;

my $PORT;

my $PASSWORD;

for (my $i = 1; $ENV{"host$i"}; $i++)

{

    $HOST = exists $ENV{"host$i"} ? $ENV{"host$i"} : "127.0.0.1";

    $PORT = exists $ENV{"port$i"} ? $ENV{"port$i"} : 6379;

    $PASSWORD = exists $ENV{"password$i"} ? $ENV{"password$i"} : undef;

    my $TITLE_PREFIX = exists $ENV{"title_prefix$i"} ? $ENV{"title_prefix$i"} . ": " : "";

    my $SOCK = &get_conn();

    $INSTANCES{"instance$i"} = {

        HOST => $HOST,

        PORT => $PORT,

        PASSWORD => $PASSWORD,

        TITLE_PREFIX => $TITLE_PREFIX,

        SOCK => $SOCK

    };

}

my $config = ( defined $ARGV[0] and $ARGV[0] eq "config" );

my $autoconf = ( defined $ARGV[0] and $ARGV[0] eq "autoconf" );

if ( $autoconf ) {

    my $err = '';

    for my $INSTANCE (keys %INSTANCES) {

        if (! defined( $INSTANCES{$INSTANCE}{'SOCK'} ) ) {

            $err .= "no (unable to connect to ".$INSTANCES{$INSTANCE}{'HOST'}."\[:". $INSTANCES{$INSTANCE}{'PORT'}."\])\n";

        }

    }

    if ($err) {

        print $err;

    } else {

        print 'yes';

    }

    exit 0;

}

my $total = 0;

my $multi_graph_output = "multigraph redis\n";

my $instance_graph_output = '';

my $connected_clients = 0;

my $keyspace_hits = 0;

my $keyspace_misses = 0;

my $expired_keys = 0;

my $evicted_keys = 0;

my $total_commands_processed = 0;

my $total_connections_received = 0;

my $repl_backlog_size = 0;

my $used_memory = 0;

my $used_memory_rss = 0;

my $used_memory_peak = 0;

my $total_keys = 0;

my $total_expires = 0;

foreach my $INSTANCE (keys %INSTANCES) {

    my $sock = $INSTANCES{$INSTANCE}{'SOCK'};

    my $TITLE_PREFIX = $INSTANCES{$INSTANCE}{'TITLE_PREFIX'};

    my $hash = get_info($sock);

    my $dbs;

    foreach my $key (keys %{$hash}) {

        if ( $key =~ /^db\d+$/ && $hash->{$key} =~ /keys=(\d+),expires=(\d+)/ ) {

            $total_keys += $1;

            $total_expires += $2;

            $dbs->{$key} = [ $1, $2 ];

        }

    }

    if ( $config ) {

        my $ret = get_config("maxclients", $sock);

        # if the CONFIG command is disabled we don't show the max clients

        my $maxclients = defined $ret ? $ret->{"maxclients"} : 0;

        $instance_graph_output .=  "multigraph redis_connected_clients.$INSTANCE\n";

        $instance_graph_output .=  "graph_title ${TITLE_PREFIX}Connected clients\n";

        $instance_graph_output .=  "graph_vlabel Connected clients\n";

        $instance_graph_output .=  "graph_category db\n";

        $instance_graph_output .=  "graph_args -l 0\n";

        if ($maxclients) {

            $instance_graph_output .=  "connected_clients.line $maxclients:ff0000:Limit\n";

        }

        $instance_graph_output .=  "connected_clients.label connected clients\n";

        $instance_graph_output .=  "multigraph keys_per_sec.$INSTANCE\n";

        $instance_graph_output .=  "graph_title ${TITLE_PREFIX}Keys Per Second\n";

        $instance_graph_output .=  "graph_vlabel per \${graph_period}\n";

        $instance_graph_output .=  "graph_category db\n";

        $instance_graph_output .=  "graph_args -l 0\n";

        $instance_graph_output .=  "hits.label hits\n";

        $instance_graph_output .=  "hits.type COUNTER\n";

        $instance_graph_output .=  "misses.label misses\n";

        $instance_graph_output .=  "misses.type COUNTER\n";

        $instance_graph_output .=  "expired.label expirations\n";

        $instance_graph_output .=  "expired.type COUNTER\n";

        $instance_graph_output .=  "evicted_keys.label evictions\n";

        $instance_graph_output .=  "evicted_keys.type COUNTER\n";

        $instance_graph_output .=  "multigraph redis_key_ratio.$INSTANCE\n";

        $instance_graph_output .=  "graph_title ${TITLE_PREFIX}Key Hit vs Miss Ratio\n";

        $instance_graph_output .=  "graph_vlabel per \${graph_period}\n";

        $instance_graph_output .=  "graph_category db\n";

        $instance_graph_output .=  "graph_args -u 100 -l 0 -r --base 1000\n";

        $instance_graph_output .=  "hitratio.label hit ratio\n";

        $instance_graph_output .=  "hitratio.type GAUGE\n";

        $instance_graph_output .=  "hitratio.draw AREA\n";

        $instance_graph_output .=  "missratio.label miss ratio\n";

        $instance_graph_output .=  "missratio.type GAUGE\n";

        $instance_graph_output .=  "missratio.draw STACK\n";

        $instance_graph_output .=  "multigraph redis_per_sec.$INSTANCE\n";

        $instance_graph_output .=  "graph_title ${TITLE_PREFIX}Requests Per second\n";

        $instance_graph_output .=  "graph_vlabel per \${graph_period}\n";

        $instance_graph_output .=  "graph_category db\n";

        $instance_graph_output .=  "graph_args -l 0\n";

        $instance_graph_output .=  "requests.label requests\n";

        $instance_graph_output .=  "requests.type COUNTER\n";

        $instance_graph_output .=  "connections.label connections\n";

        $instance_graph_output .=  "connections.type COUNTER\n";

        $instance_graph_output .=  "multigraph redis_repl_backlog_size.$INSTANCE\n";

        $instance_graph_output .=  "graph_title ${TITLE_PREFIX}replication backlog\n";

        $instance_graph_output .=  "graph_vlabel replication backlog\n";

        $instance_graph_output .=  "graph_category db\n";

        $instance_graph_output .=  "graph_args -l 0\n";

        $instance_graph_output .=  "repl_backlog_size.label bytes behind master\n";

        $instance_graph_output .=  "multigraph redis_repl_lag.$INSTANCE\n";

        $instance_graph_output .=  "graph_title ${TITLE_PREFIX}replication lag\n";

        $instance_graph_output .=  "graph_vlabel replication lag\n";

        $instance_graph_output .=  "graph_category db\n";

        $instance_graph_output .=  "graph_args -l 0\n";

        $instance_graph_output .=  "repl_backlog_size.label amount behind master\n";

        # if the CONFIG command is disabled we don't show maxmemory

        $ret = get_config("maxmemory", $sock);

        my $maxmemory = defined $ret ? $ret->{"maxmemory"} : 0;

        $instance_graph_output .=  "multigraph redis_used_memory.$INSTANCE\n";

        $instance_graph_output .=  "graph_title ${TITLE_PREFIX}Used memory\n";

        $instance_graph_output .=  "graph_vlabel Used memory\n";

        $instance_graph_output .=  "graph_category db\n";

        $instance_graph_output .=  "graph_args -l 0 --base 1024\n";

        if ($maxmemory) {

            $instance_graph_output .=  "used_memory.line $maxmemory:ff0000:Limit\n";

        }

        $instance_graph_output .=  "used_memory.label used memory\n";

        $instance_graph_output .=  "used_memory_peak.label used memory in peak\n";

        $instance_graph_output .=  "used_memory_rss.label Resident set size memory usage\n";

        $instance_graph_output .=  "multigraph redis_used_keys.$INSTANCE\n";

        $instance_graph_output .=  "graph_title ${TITLE_PREFIX}Used keys\n";

        $instance_graph_output .=  "graph_vlabel Used keys\n";

        $instance_graph_output .=  "graph_category db\n";

        $instance_graph_output .=  "graph_args -l 0\n";

        foreach my $db (keys %{$dbs}) {

            $instance_graph_output .= sprintf "%s_keys.label %s keys\n", $db, $db;

            $instance_graph_output .= sprintf "%s_expires.label %s expires\n", $db, $db;

        }

        next;

    }

    $instance_graph_output .=  "multigraph redis_connected_clients.$INSTANCE\n";

    $instance_graph_output .=  "connected_clients.value " . $hash->{'connected_clients'} . "\n";

    $connected_clients += $hash->{'connected_clients'}; 

    $instance_graph_output .=  "multigraph keys_per_sec.$INSTANCE\n";

    $instance_graph_output .=  "hits.value " . $hash->{'keyspace_hits'} . "\n";

    $keyspace_hits += $hash->{'keyspace_hits'};

    $instance_graph_output .=  "misses.value " . $hash->{'keyspace_misses'} . "\n";

    $keyspace_misses += $hash->{'keyspace_misses'};

    $instance_graph_output .=  "expired.value " . $hash->{'expired_keys'} . "\n";

    $expired_keys += $hash->{'expired_keys'};

    $instance_graph_output .=  "evicted_keys.value " . $hash->{'evicted_keys'} . "\n";

    $evicted_keys += $hash->{'evicted_keys'};

    $instance_graph_output .=  "multigraph redis_key_ratio.$INSTANCE\n";

    my $total = $hash->{'keyspace_hits'} + $hash->{'keyspace_misses'};

    my $hitratio = 0;

    my $missratio = 0;

    if ($total > 0) {

        $hitratio = $hash->{'keyspace_hits'} / $total * 100;

        $missratio = $hash->{'keyspace_misses'} / $total * 100;

    }

    $instance_graph_output .= sprintf("hitratio.value %.2f\n", $hitratio);

    $instance_graph_output .= sprintf("missratio.value %.2f\n", $missratio);

    $instance_graph_output .=  "multigraph redis_per_sec.$INSTANCE\n";

    $instance_graph_output .=  "requests.value ". $hash->{'total_commands_processed'} ."\n";

    $total_commands_processed += $hash->{'total_commands_processed'};

    $instance_graph_output .=  "connections.value ". $hash->{'total_connections_received'} ."\n";

    $total_connections_received += $hash->{'total_connections_received'};

    $instance_graph_output .=  "multigraph redis_repl_backlog_size.$INSTANCE\n";

    $instance_graph_output .=  "repl_backlog_size.value " . $hash->{'repl_backlog_size'} . "\n";

    $repl_backlog_size += $hash->{'repl_backlog_size'};

    $instance_graph_output .=  "multigraph redis_repl_lag.$INSTANCE\n";

    if (exists $hash->{slave0} && $hash->{slave0} =~ /lag=(\d+)/) { 

        $repl_backlog_size += $1;

        $instance_graph_output .=  "repl_backlog_size.value " . $1 . "\n";

    } else {

        $instance_graph_output .=  "repl_backlog_size.value 0\n";

    }

    $instance_graph_output .=  "multigraph redis_used_memory.$INSTANCE\n";

    $instance_graph_output .=  "used_memory.value ". $hash->{'used_memory'}  ."\n";

    $used_memory += $hash->{'used_memory'};

    $instance_graph_output .=  "used_memory_rss.value ". $hash->{'used_memory_rss'}  ."\n";

    $used_memory_rss += $hash->{'used_memory_rss'};

    $instance_graph_output .=  "used_memory_peak.value ". $hash->{'used_memory_peak'}  ."\n";

    $used_memory_peak += $hash->{'used_memory_peak'};

    $instance_graph_output .=  "multigraph redis_used_keys.$INSTANCE\n";

    foreach my $db (keys %{$dbs}) {

        $instance_graph_output .= sprintf "%s_keys.value %d\n", $db, $dbs->{$db}[0];

        $instance_graph_output .= sprintf "%s_expires.value %d\n", $db, $dbs->{$db}[1];

    }

    close ($sock);

}

# multigraph output

if ($config) {

    $multi_graph_output .=  "multigraph redis_connected_clients\n";

    $multi_graph_output .=  "graph_title Connected clients\n";

    $multi_graph_output .=  "graph_vlabel Connected clients\n";

    $multi_graph_output .=  "graph_category db\n";

    $multi_graph_output .=  "graph_args -l 0\n";

    $multi_graph_output .=  "connected_clients.label connected clients\n";

    $multi_graph_output .=  "multigraph keys_per_sec\n";

    $multi_graph_output .=  "graph_title Keys Per Second\n";

    $multi_graph_output .=  "graph_vlabel per \${graph_period}\n";

    $multi_graph_output .=  "graph_category db\n";

    $multi_graph_output .=  "graph_args -l 0\n";

    $multi_graph_output .=  "hits.label hits\n";

    $multi_graph_output .=  "hits.type COUNTER\n";

    $multi_graph_output .=  "misses.label misses\n";

    $multi_graph_output .=  "misses.type COUNTER\n";

    $multi_graph_output .=  "expired.label expirations\n";

    $multi_graph_output .=  "expired.type COUNTER\n";

    $multi_graph_output .=  "evicted_keys.label evictions\n";

    $multi_graph_output .=  "evicted_keys.type COUNTER\n";

    $multi_graph_output .=  "multigraph redis_key_ratio\n";

    $multi_graph_output .=  "graph_title Key Hit vs Miss Ratio\n";

    $multi_graph_output .=  "graph_vlabel per \${graph_period}\n";

    $multi_graph_output .=  "graph_category db\n";

    $multi_graph_output .=  "graph_args -u 100 -l 0 -r --base 1000\n";

    $multi_graph_output .=  "hitratio.label hit ratio\n";

    $multi_graph_output .=  "hitratio.type GAUGE\n";

    $multi_graph_output .=  "hitratio.draw AREA\n";

    $multi_graph_output .=  "missratio.label miss ratio\n";

    $multi_graph_output .=  "missratio.type GAUGE\n";

    $multi_graph_output .=  "missratio.draw STACK\n";

    $multi_graph_output .=  "multigraph redis_per_sec\n";

    $multi_graph_output .=  "graph_title Requests Per second\n";

    $multi_graph_output .=  "graph_vlabel per \${graph_period}\n";

    $multi_graph_output .=  "graph_category db\n";

    $multi_graph_output .=  "graph_args -l 0\n";

    $multi_graph_output .=  "requests.label requests\n";

    $multi_graph_output .=  "requests.type COUNTER\n";

    $multi_graph_output .=  "connections.label connections\n";

    $multi_graph_output .=  "connections.type COUNTER\n";

    $multi_graph_output .=  "multigraph redis_repl_backlog_size\n";

    $multi_graph_output .=  "graph_title replication backlog\n";

    $multi_graph_output .=  "graph_vlabel replication backlog\n";

    $multi_graph_output .=  "graph_category db\n";

    $multi_graph_output .=  "graph_args -l 0\n";

    $multi_graph_output .=  "repl_backlog_size.label bytes behind master\n";

    $multi_graph_output .=  "multigraph redis_repl_lag\n";

    $multi_graph_output .=  "graph_title replication lag\n";

    $multi_graph_output .=  "graph_vlabel replication lag\n";

    $multi_graph_output .=  "graph_category db\n";

    $multi_graph_output .=  "graph_args -l 0\n";

    $multi_graph_output .=  "repl_backlog_size.label amount behind master\n";

    $multi_graph_output .=  "multigraph redis_used_memory\n";

    $multi_graph_output .=  "graph_title Used memory\n";

    $multi_graph_output .=  "graph_vlabel Used memory\n";

    $multi_graph_output .=  "graph_category db\n";

    $multi_graph_output .=  "graph_args -l 0 --base 1024\n";

    $multi_graph_output .=  "used_memory.label used memory\n";

    $multi_graph_output .=  "used_memory_peak.label used memory in peak\n";

    $multi_graph_output .=  "used_memory_rss.label Resident set size memory usage\n";

    $multi_graph_output .=  "multigraph redis_used_keys\n";

    $multi_graph_output .=  "graph_title Used keys\n";

    $multi_graph_output .=  "graph_vlabel Used keys\n";

    $multi_graph_output .=  "graph_category db\n";

    $multi_graph_output .=  "graph_args -l 0\n";

    $multi_graph_output .=  "total_keys.label Total keys\n";

    $multi_graph_output .=  "total_expires.label Total expires\n";

} else {

    $multi_graph_output .=  "multigraph redis_connected_clients\n";

    $multi_graph_output .=  "connected_clients.value " . $connected_clients . "\n";

    $multi_graph_output .=  "multigraph keys_per_sec\n";

    $multi_graph_output .=  "hits.value " . $keyspace_hits . "\n";

    $multi_graph_output .=  "misses.value " . $keyspace_misses . "\n";

    $multi_graph_output .=  "expired.value " . $expired_keys . "\n";

    $multi_graph_output .=  "evicted_keys.value " . $evicted_keys . "\n";

    $multi_graph_output .=  "multigraph redis_key_ratio\n";

    my $total = $keyspace_hits + $keyspace_misses;

    my $hitratio = 0;

    my $missratio = 0;

    if ($total > 0) {

        $hitratio = $keyspace_hits / $total * 100;

        $missratio = $keyspace_misses / $total * 100;

    }

    $multi_graph_output .= sprintf("hitratio.value %.2f\n", $hitratio);

    $multi_graph_output .= sprintf("missratio.value %.2f\n", $missratio);

    $multi_graph_output .=  "multigraph redis_per_sec\n";

    $multi_graph_output .=  "requests.value ". $total_commands_processed ."\n";

    $multi_graph_output .=  "connections.value ". $total_connections_received ."\n";

    $multi_graph_output .=  "multigraph redis_repl_backlog_size\n";

    $multi_graph_output .=  "repl_backlog_size.value " . $repl_backlog_size . "\n";

    $multi_graph_output .=  "multigraph redis_repl_lag\n";

    $multi_graph_output .=  "repl_backlog_size.value " . $repl_backlog_size  . "\n";

    $multi_graph_output .=  "multigraph redis_used_memory\n";

    $multi_graph_output .=  "used_memory.value ". $used_memory  ."\n";

    $multi_graph_output .=  "used_memory_rss.value ". $used_memory_rss  ."\n";

    $multi_graph_output .=  "used_memory_peak.value ". $used_memory_peak  ."\n";

    $multi_graph_output .=  "multigraph redis_used_keys\n";

    $multi_graph_output .=  "total_keys.value $total_keys\n";

    $multi_graph_output .=  "total_expires.value $total_expires\n";

}

print $multi_graph_output;

print $instance_graph_output;

sub get_conn {

    my $sock;

    if(-S $HOST ){

        $sock = IO::Socket::UNIX->new(

            Type => SOCK_STREAM(),

            Peer => $HOST,

        );

    }else{

        $sock = IO::Socket::INET->new(

            PeerAddr => $HOST,

            PeerPort => $PORT,

            Timeout => 10,

            Proto => 'tcp'

        );

    }

	if (! defined($sock)) {

         die "can't read socket: $!";

	}

    if ( defined( $PASSWORD )  ) {

        print $sock "AUTH ", $PASSWORD, "\r\n";

        my $result = <$sock> || die "can't read socket: $!";

    }

    return $sock;

}

sub get_info{

    my $sock = $_[0];

    print $sock "INFO\r\n";

    my $result = <$sock> || die "can't read socket: $!";

    my $rep;

    # +2 characters for \r\n at end of the data block

    read($sock, $rep, substr($result,1)+2) || die "can't read from socket: $!";

    my $hash;

    foreach (split(/\r\n/, substr($rep, 0, -2))) {

        my ($key,$val) = split(/:/, $_, 2);

        if (defined($key)) {

            $hash->{$key} = $val;

        }

    }

    return $hash;

}

# This subroutine returns configuration matched to supplied as object

sub get_config{

    my $sock = $_[1];

    print $sock "*3\r\n\$6\r\nCONFIG\r\n\$3\r\nGET\r\n\$".length($_[0])."\r\n".$_[0]."\r\n";

    # Response will look like like

    # *2\r\n$9\r\nmaxmemory\r\n$10\r\n3221225472\r\n

    my $type = <$sock> || die "can't read socket: $!";

    my $conf;

    if( substr($type,0,1) ne "*" ) {

        return $conf;

    }

    my $count=substr($type,1);

    my ( $namesize, $name, $valuesize, $value );

    while ( $count > 1 ){

        $count=$count-2;

        $namesize=<$sock>;

        read($sock, $name, substr($namesize,1)+2) || die "can't read from socket: $!";

        $valuesize=<$sock>;

        read($sock, $value, substr($valuesize,1)+2) || die "can't read from socket: $!";

        $conf->{substr($name, 0, -2)}=substr($value, 0, -2);

    }

    return $conf;

}

# vim: ft=perl ai ts=4 sw=4 et: