Munin contributed plugins

#!/bin/bash

# (c) 2012  - Bushmills

# License : GPLv2

#%# family=auto

#%# capabilities=autoconf

interval=1			# mpstat sampling interval

timeout=1200			# 20 minutes daemon watchdog timeout

watchdog=60			# test for timeout every $watchdog seconds

pluginfull="$0"                 # full name of plugin

plugin="${0##*/}"	        # name of plugin

pidfile="$MUNIN_PLUGSTATE/munin.$plugin.pid"

cache="$MUNIN_PLUGSTATE/munin.$plugin.value"

graph="$plugin"

style="AREA"

cpus=$(grep -c ^processor /proc/cpuinfo)

run_watchdog()  {                 # should also trap kill and term signals

   kill -0 $(cat $pidfile) 2> /dev/null || rm -f $pidfile

}

run_acquire()  {

   echo "$$" > $pidfile

   LANG=C mpstat -P ALL $interval |

   awk -v cpus=$cpus '$2>=0&&$2<99 {print $2, systime(), (100-$11)/cpus; system("");}' >> $cache

   rm -f $pidfile $cache

}

run_daemon()  {

   run_watchdog

   if [ -f $pidfile ]; then

      touch $pidfile

   else

      $pluginfull acquire &

   fi

}

# --------------------------------------------------------------------------

run_autoconf() {

   run=(yes no)

   type -t mpstat > /dev/null

   echo "${run[$?]}"

}

run_config() {

run_daemon

cat << EOF

graph_title $graph

graph_category 1sec

graph_vlabel average 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

EOF

cpun=0

for ((i=0; i<$cpus; i++)); do

cat << EOF

cpu${cpun}.label CPU $cpun

cpu${cpun}.draw $style

cpu${cpun}.min 0

EOF

style=STACK

((cpun++))

done

}

run_fetch()  {

   run_daemon

   awk 'NF==3 {print "cpu" $1 ".value " $2 ":" $3}' $cache

   > $cache

}

run_${1:-fetch}

exit 0

# export -f functionname     export functionname to subshell, avoiding the need

#    for locating plugin for subshell calling, when process needs a different

#    pid. Instead, $SHELL -c functionname  can be used. useful for calling

#    acquire which needs a different pid than watchdog, otherwise watchdog

#    could/will kill itself when expiring before the watched process is killed.

# not a POSIX feature.