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check_cpu 7.33 KiB
#!/bin/bash
# ======================================================================
#
# Check CPU usage
#
# requirements:
# - top
# - bc
#
# ----------------------------------------------------------------------
# 2020-03-10  v1.0  <axel.hahn@iml.unibe.ch>
# 2020-03-23  v1.1  <axel.hahn@iml.unibe.ch> added more data
# 2020-07-08  v1.2  <axel.hahn@iml.unibe.ch> FIX: set "ph." instead "ps."
# 2020-07-17  v1.3  <axel.hahn@iml.unibe.ch> use ph.require to check binaries
# 2021-02-10  v1.4  <axel.hahn@iml.unibe.ch> added critical io wait
# 2021-10-28  v1.5  <axel.hahn@iml.unibe.ch> Use 2nd update of top
# 2021-12-10  v1.6  <axel.hahn@iml.unibe.ch> show processes with status D to find cpu waits
# 2022-03-09  v1.7  <axel.hahn@iml.unibe.ch> show most cpu intensive processes
# 2022-03-10  v1.8  <axel.hahn@iml.unibe.ch> add cli param -p; update help
# 2022-03-22  v1.9  <axel.hahn@iml.unibe.ch> fix syntax error on 100% idle
# 2022-04-14  v1.10 <axel.hahn@iml.unibe.ch> show consuming cpu processes with top and ps
# ======================================================================


. $(dirname $0)/inc_pluginfunctions

self_APPNAME=$( basename $0 | tr [:lower:] [:upper:] )
self_APPVERSION=1.9

# ----------------------------------------------------------------------
# functions
# ----------------------------------------------------------------------

function showHelp(){
cat <<EOF
______________________________________________________________________

$self_APPNAME 
v$self_APPVERSION

(c) Institute for Medical Education - University of Bern
Licence: GNU GPL 3
______________________________________________________________________

check cpu usage and cpu wait
Cpu infos are taken from output of top command.

SYNTAX:
$(basename $0) [-w WARN_LIMIT] [-c CRITICAL_LIMIT] [-i CRITICAL_IO_WAIT] [-p PROCESS_LIMIT]

OPTIONS:

    -w VALUE       cpu usage warning level  (default: 75)
    -c VALUE       cpu usage critical level (default: 90)

    -i VALUE       io wait critical level   (default: 50)

    -p VALUE       show process info with highest cpu consumption if 
                   usage is > NN %; default: 50

    -h or --help   show this help.

PARAMETERS:

    None.

EXAMPLE:
$(basename $0) -w 60 -c 80 -p 40

EOF
}
# ----------------------------------------------------------------------
# MAIN
# ----------------------------------------------------------------------

# --- check required tools
ph.require bc top


# --- check param -h
case "$1" in
    "--help"|"-h")
        showHelp
        exit 0
        ;;
    *)
esac

# ----------------------------------------------------------------------
# set default / override from command line params
typeset -i iWarnLimit=$(     ph.getValueWithParam 75 w "$@")
typeset -i iCriticalLimit=$( ph.getValueWithParam 90 c "$@")
typeset -i iCriticalWait=$(  ph.getValueWithParam 50 i "$@")
typeset -i iMinCpuUsageToShowProcesses=$(  ph.getValueWithParam 50 p "$@")

# ----------------------------------------------------------------------
# get data

# get cpu status i.e.
# %Cpu(s): 33.3 us,  9.5 sy,  0.0 ni, 57.1 id,  0.0 wa,  0.0 hi,  0.0 si,  0.0 st
#   us, user    : time running un-niced user processes
#   sy, system  : time running kernel processes
#   ni, nice    : time running niced user processes
#   id, idle    : time spent in the kernel idle handler
#   wa, IO-wait : time waiting for I/O completion
#   hi : time spent servicing hardware interrupts
#   si : time spent servicing software interrupts
#   st : time stolen from this vm by the hypervisor
# top -b -n 1 | head -5 | grep "^\%Cpu" >$tmpfile
# FIX read cpu from 2nd output of top

data=$( top -b -n 2 -d 0.1 | grep -i "^\%Cpu" | tail -1 | cut -f 2- -d ':' | tr ',' "\n" )

cpuUser=$(   echo "$data" | grep "us" | awk '{ print $1 }' )
cpuSystem=$( echo "$data" | grep "sy" | awk '{ print $1 }' )
cpuNice=$(   echo "$data" | grep "ni" | awk '{ print $1 }' )
cpuIdle=$(   echo "$data" | grep "id" | awk '{ print $1 }' )
cpuWait=$(   echo "$data" | grep "wa" | awk '{ print $1 }' )
cpuHi=$(     echo "$data" | grep "hi" | awk '{ print $1 }' )
cpuSi=$(     echo "$data" | grep "si" | awk '{ print $1 }' )
cpuSt=$(     echo "$data" | grep "st" | awk '{ print $1 }' )

cpuNonIdle=$(echo 100-$cpuIdle | bc)

sInfo="INFO  : cpu is in normal ranges."
if [ "$(echo "${cpuWait} > ${iCriticalWait}" | bc)" -eq 1 ]; then
  ph.setStatus "critical"
  sInfo="HINT  : cpu WAIT is high - check hardware issues"
else
  if [ "$(echo "${cpuNonIdle} > ${iWarnLimit}" | bc)" -eq 1 ]; then

      if [ "$(echo "${cpuNonIdle} > ${iCriticalLimit}" | bc)" -eq 1 ]; then
          ph.setStatus "critical"
          sInfo="HINT  : cpu usage is high - check processes"
      else
          ph.setStatus "warning"
          sInfo="HINT  : cpu usage is high - check processes"
      fi
  fi
fi

# ----------------------------------------------------------------------
# output

# --- status output
ph.status "CPU-USAGE [%] ${cpuNonIdle} ... user: ${cpuUser} - system: ${cpuSystem} - idle: ${cpuIdle} - wait: ${cpuWait}"

# v1.6: show processes of cpu wait (status D in proces list)
plist=$( ps aux | awk '$8 ~ /(D|STAT)/ { print $0 }' )
echo "$plist" | grep "[0-9]" >/dev/null \
    && echo \
    && echo "For analysis of cpu waits - processes with status D:" \
    && echo "$plist"

# v1.7: show most consuming processes if usage is > nn %
typeset -i iUsed=$( echo $cpuNonIdle | cut -f 1 -d '.' )
if [ $iUsed -gt $iMinCpuUsageToShowProcesses ]; then
  echo
  echo "CPU usage is higher $iMinCpuUsageToShowProcesses percent ... showing most consuming processes"
  echo "output of top :"
  topout=$( top -b -n 1 -d 0.1 )
  typeset -i iStart=$( echo "$topout" | grep -n "PID.*USER" | cut -f 1 -d ':' )
  typeset -i iEnd=$iStart+5
  echo "$topout" | sed -n "${iStart},${iEnd}p"
  echo
  echo "output of ps:"
  ps aux | head -1; ps aux | sort -nrk 3,3 | head -n 5
  echo 
fi 

echo "
Limits: usage warn at ${iWarnLimit} .. critical at ${iCriticalLimit} .. io wait limit ${iCriticalWait}
$sInfo

Legend:

   hwi - Time spent handling hardware interrupt routines. (Whenever a peripheral unit want attention form the CPU, it literally pulls a line, to signal the CPU to service it)
   swi - Time spent handling software interrupt routines. (a piece of code, calls an interrupt routine...)
    st - Time spent on involuntary waits by virtual cpu while hypervisor is servicing another processor (stolen from a virtual machine)

  nice - Time spent running niced user processes (User defined priority)
  wait - Time spent on waiting on IO peripherals (eg. disk)

system - Time spent in kernel space
  user - Time spent in user space
  idle - Time spent in idle operations
"


# --- performance data usage
ph.perfadd "cpu-usage"    "${cpuNonIdle}" $iWarnLimit $iCriticalLimit 0 100

# for graphite module: send limits
# ph.perfadd "cpu-warn"     $iWarnLimit      "" "" 0 100
# ph.perfadd "cpu-crit"     $iCriticalLimit  "" "" 0 100

ph.perfadd "cpu-wait"     "${cpuWait}"     "" "$iCriticalWait" 0 100

# --- performance data single values
ph.perfadd "cpu-system"   "${cpuSystem}"   "" "" 0 100
ph.perfadd "cpu-user"     "${cpuUser}"     "" "" 0 100
ph.perfadd "cpu-idle"     "${cpuIdle}"     "" "" 0 100
ph.perfadd "cpu-nice"     "${cpuNice}"     "" "" 0 100
ph.perfadd "cpu-hwi"      "${cpuHi}"       "" "" 0 100
ph.perfadd "cpu-swi"      "${cpuSi}"       "" "" 0 100
ph.perfadd "cpu-st"       "${cpuSt}"       "" "" 0 100

ph.exit

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