Killing the daemon restarts it || Ubuntu

Im on DigitalOcean’s droplet. Ubuntu 18.4.
Installed Docker CE. Runs OK
One week ago I stopped Docker daemon with /etc/init.d/docker stop. I confirmed that it was stopped.

Now - today I just checked RAM usage to notice extremity. Overuse. 4GB out of 6GB. Holy much. Typical usage for me is around 2GB.

Quick tap-ram and what uses much? Docker. Nothing against high usage of RAM by Docker, but it was not needed as there are no containers being used/needed currently.

So I just stopped Docker by /etc/init.d/docker stop
I checked status with/etc/init.d/docker status and … it was fucking running…

How to stop Docker and prevent it from autostarting?

This reminds me to the good old Unix-Days and the standard response: RTFM!

@meyay:> so whats the rationale behind /etc/init.d/docker script than if Docker has its own?
And you misunderstood me. I asked why docker main process is unkillable? It keeps spawning once killed.