In a Debian 9 Stretch with docker 19.03.1
I'm using 6 containers and I observe swapping of 125Mo while memory usage never exceed 10% of total. ( usually around 500Mo / 16Go ).
for file in /proc/*/status ; do awk '/VmSwap|Name/{printf $2 " " $3}END{ print ""}' $file; done | sort -k 2 -n -r | less
give me the following result
dockerd 25160 kB
named 14304 kB
docker-proxy 8144 kB
containerd 7808 kB
docker-proxy 6176 kB
docker-proxy 6100 kB
docker-proxy 4068 kB
docker-proxy 4064 kB
docker-proxy 4064 kB
docker-proxy 4064 kB
docker-proxy 4060 kB
docker-proxy 4060 kB
docker-proxy 3992 kB
docker-proxy 3980 kB
docker-proxy 3940 kB
docker-proxy 3940 kB
docker-proxy 3880 kB
docker-proxy 3824 kB
fail2ban-server 3400 kB
docker-proxy 3088 kB
docker-proxy 2060 kB
It seems docker is swapping a lot. How can i find which container is swapping my host system and how to prevent it ?
Thanks.