how to monitor docker containers resource usage using shell script - docker

Question

how to monitor docker containers resource usage using a shell script.
I was just wondering can we use the docker stats command to get metrics to monitor docker containers resource usage

Answer 1

I have written a small shell script that will help to filter docker containers that are using max system resources. (I guess will work for one docker-swarm node cluster)
#!/bin/bash
#This script is used to complete the output of the docker stats command.
#The docker stats command does not compute the total amount of resources (RAM or CPU)
#Get the total amount of RAM, assumes there are at least 1024*1024 KiB, therefore > 1 GiB
docker stats | while read line
do
HOST_MEM_TOTAL=$(grep MemTotal /proc/meminfo | awk '{print $2/1024/1024}')
#echo "HOST TOTAL Memory: $HOST_MEM_TOTAL"
oldifs=IFS
IFS=;
dStats=$(docker stats --no-stream --format "table {{.MemPerc}}\t{{.CPUPerc}}\t{{.MemUsage}}\t{{.Name}}\t{{.ID}}" | sed -n '1!p')
#dStats=$( docker stats --no-stream --format "table {{.MemPerc}}\t{{.CPUPerc}}\t{{.MemUsage}}\t{{.Name}}\t{{.ID}}")
SUM_RAM=`echo $dStats | tail -n +2 | sed "s/%//g" | awk '{s+=$1} END {print s}'`
SUM_CPU=`echo $dStats | tail -n +2 | sed "s/%//g" | awk '{s+=$2} END {print s}'`
SUM_RAM_QUANTITY=`LC_NUMERIC=C printf %.2f $(echo "$SUM_RAM*$HOST_MEM_TOTAL*0.01" | bc)`
# Output the result
echo "########################################### Start of Resources Output ##############################################" >> /tmp/emailFiles/Docker-Resources-Usage-Stats.txt
echo " " >> /tmp/emailFiles/Docker-Resources-Usage-Stats.txt
dat=$(date)
echo "Present date & Time is: $dat" >> /tmp/emailFiles/Docker-Resources-Usage-Stats.txt
#IFS=$olifs
#echo "MEM % CPU % MEM USAGE / LIMIT NAME CONTAINER ID" >> /tmp/emailFiles/Docker-Resources-Usage-Stats.txt
echo "MEM % CPU % MEM USAGE / LIMIT NAME CONTAINER ID" >> /tmp/emailFiles/Docker-Resources-Usage-Stats.txt
IFS=$'\r\n' GLOBIGNORE='*'
for i in $dStats
do
cpuPerc=$(echo $i | awk '{print $2}')
memPerc=$(echo $i | awk '{print $1}')
cpuPerc=${cpuPerc%"%"}
cpuPerc=${cpuPerc/.*}
memPerc=${memPerc%"%"}
memPerc=${memPerc/.*}
#if [ $cpuPerc -ge 100 ] && [ $memPerc -ge 35 ]
if [ $cpuPerc -ge 100 ] || [ $memPerc -ge 50 ]
then
#IFS=$oldifs
echo $i >> /tmp/emailFiles/Docker-Resources-Usage-Stats.txt
else
a="hello"
fi
done
#IFS=$oldifs
SUM_RAM=${SUM_RAM/.*}
SUM_CPU=${SUM_CPU/.*}
if [ $SUM_RAM -ge 70 ] && [ $SUM_CPU -ge 100 ]
#if [ $SUM_RAM -ge 70 ] || [ $SUM_CPU -ge 100 ]
then
echo " " >>/tmp/emailFiles/Docker-Resources-Usage-Stats.txt
echo "Total-MEMORY-Usage Total-CPU-Usage Used-MEM / Total-MEM" >> /tmp/emailFiles/SIMSAPP-Docker-Resources-Usage-Stats.txt
#echo -e "${SUM_RAM}%\t\t\t${SUM_CPU}%\t\t${SUM_RAM_QUANTITY}GiB / ${HOST_MEM_TOTAL}GiB\tTOTAL" >> /tmp/emailFiles/Docker-Resources-Usage-Stats.txt
echo -e "${SUM_RAM}%\t\t\t${SUM_CPU}%\t\t${SUM_RAM_QUANTITY}GiB / ${HOST_MEM_TOTAL}GiB" >> /tmp/emailFiles/Docker-Resources-Usage-Stats.txt
echo " ">>/tmp/emailFiles/Docker-Resources-Usage-Stats.txt
fi
disk_usage=$(df -hT | grep ext4 | awk '{print $6}')
#disk_usage=$(df -kv| grep sda1 | awk '{preint $5}')
disk_usage=${disk_usage%"%"}
#disk_usage=${disk_usage/.*}
if [ $disk_usage -ge 90 ]
then
#echo "Filesystem Size Used Avail Use% Mounted on" >>/tmp/emailFiles/Docker-Resources-Usage-Stats.txt
echo "Filesystem Type Size Used Avail Use% Mounted on" >> /tmp/emailFiles/Docker-Resources-Usage-Stats.txt
#df -kh | grep sda1 >> /tmp/emailFiles/Docker-Resources-Usage-Stats.txt
df -hT | grep ext4 >> /tmp/emailFiles/Docker-Resources-Usage-Stats.txt
echo " "
#cat /tmp/emailFiles/Docker-Resources-Usage-Stats.txt
fi
echo "########################################### End of Resources Output ################################################" >> /tmp/emailFiles/Docker-Resources-Usage-Stats.txt
echo " " >> /tmp/emailFiles/Docker-Resources-Usage-Stats.txt
done
Please modify it according to your requirement, if you find it useful.