vmstat_monitor

vmstat_monitor.sh

#!/bin/bash
###############################################################################
# vmstat_monitor.sh
#
# Options:
#   $1  Delay, in seconds, between readings. Must be >0
#   $2  Count of readings to take. This should always be 2
#
# If the VMSTAT_DEBUG variable is set non-empty, debug output of all values of
# variables will be outputed to stderr.
###############################################################################

#################
# Configuration #
###############################################################################

DEFAULT_DELAY=1
DEFAULT_COUNT=2

#############
# Functions #
###############################################################################

get_vmstat ()
{
    local delay=${1:-1}
    local count=${2:-2}
    
    local vmstat_output=$(vmstat ${delay} ${count})
    
    if [ -n "$VMSTAT_DEBUG" ]
    then
        echo >&2 "<vmstat delay=${delay} count=${count}>"
        echo >&2 "$vmstat_output"
        echo >&2 "</vmstat>"
    fi
    
    echo "$vmstat_output" | tail -n 1
}

#############
# Execution #
###############################################################################

DELAY=${1:-${DEFAULT_DELAY}}
COUNT=${2:-${DEFAULT_COUNT}}

VMSTAT=( $(get_vmstat ${DELAY} ${COUNT}) )

# See `man vmstat` for details on the below values and
# ensure to run once with VMSTAT_DEBUG to sanity check
# that the values are correct for your system.

PROCS_R=${VMSTAT[0]}
PROCS_B=${VMSTAT[1]}

MEM_SWPD=${VMSTAT[2]}
MEM_FREE=${VMSTAT[3]}
MEM_BUFF=${VMSTAT[4]}
MEM_CACHE=${VMSTAT[5]}

SWAP_SI=${VMSTAT[6]}
SWAP_SO=${VMSTAT[7]}

IO_BI=${VMSTAT[8]}
IO_BO=${VMSTAT[9]}

# These are reported in units per second
SYSTEM_IN=${VMSTAT[10]}
SYSTEM_CS=${VMSTAT[11]}

CPU_US=${VMSTAT[12]}
CPU_SY=${VMSTAT[13]}
CPU_ID=${VMSTAT[14]}
CPU_WA=${VMSTAT[15]}
CPU_ST=${VMSTAT[16]}

if [ -n "$VMSTAT_DEBUG" ]
then
    echo -e "VMSTAT:\t${VMSTAT[@]}" >&2 
    for v in PROCS_{R,B} \
             MEM_{SWPD,FREE,BUFF,CACHE,INACT,ACTIVE} \
             SWAP_{SI,SO} \
             IO_{BI,BO} \
             SYSTEM_{IN,CS} \
             CPU_{US,SY,ID,WA,ST}
     do
        echo -e "${v}:\t${!v}" >&2 
    done
fi

########
# TODO #
###############################################################################
# Format your output for whatever monitoring tool you're using such as Zabbix,
# Nagios, Centreon, etc.
###############################################################################