#!/bin/bash
# -*- sh -*-

: << =cut

=head1 NAME

zram - Plugin to monitor zram usage

=head1 CONFIGURATION

No configuration

=head1 AUTHOR

Unknown author

=head1 LICENSE

GPLv2

=head1 MAGIC MARKERS

 #%# family=auto
 #%# capabilities=autoconf

=cut

. $MUNIN_LIBDIR/plugins/plugin.sh

if [ "$1" = "autoconf" ]; then
        if [ -r /sys/block/zram0 ]; then
                echo yes
                exit 0
        else
                echo "no (no zram device)"
                exit 0
        fi
fi

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

        echo 'multigraph zram_usage'
        echo 'graph_title zram usage'
        echo 'graph_vlabel bytes'
        echo 'graph_category system'
        echo 'disksize.label size'
        echo 'used.label used'
        echo 'compressed.label compressed'
        echo 'memory_used.label memory_used'
        echo
        echo 'multigraph zram_efficiency'
        echo 'graph_title zram efficiency'
        echo "graph_args -r --lower-limit 0 --upper-limit 100"
        echo 'graph_vlabel compression efficiency'
        echo 'graph_category system'
        echo 'efficiency.label efficiency %'
        exit 0
fi

# Zram Location
ZL="/sys/block/zram*"

used=$(cat $ZL/mm_stat | awk '{s+=$1} END {print s}')
memory_used=$(cat $ZL/mm_stat | awk '{s+=$3} END {print s}')
disksize=$(cat $ZL/disksize | awk '{s+=$1} END {print s}')
compressed=$(cat $ZL/mm_stat | awk '{s+=$2} END {print s}')

efficiency=$(echo "scale=2; 100 - $memory_used * 100 / $used" | bc -l)

echo 'multigraph zram_usage'
echo "disksize.value $disksize"
echo "used.value $used"
echo "compressed.value $compressed"
echo "memory_used.value $memory_used"
echo
echo "multigraph zram_efficiency"
echo "efficiency.value $efficiency"