docker-q.txt

good morning - I had a docker daemon running on a digital ocean droplet and uh, it kind of just crapped out on me after a while... I was unable to get the docker service running again through systemd
if I run a systemctl status on the service, I see logs like -

● docker.service - Docker Application Container Engine
   Loaded: loaded (/lib/systemd/system/docker.service; enabled; vendor preset: enabled)
   Active: activating (start) since Sat 2018-04-28 15:58:22 UTC; 59s ago
     Docs: https://docs.docker.com
 Main PID: 2738 (dockerd)
    Tasks: 8
   Memory: 390.8M
      CPU: 29.409s
   CGroup: /system.slice/docker.service
           └─2738 /usr/bin/dockerd -H fd://

Apr 28 15:58:42 play dockerd[2738]: time="2018-04-28T15:58:42.622871326Z" level=info msg="Graph migration to content-addressability took 0.00 seconds"
Apr 28 15:58:42 play dockerd[2738]: time="2018-04-28T15:58:42.624045233Z" level=warning msg="Your kernel does not support swap memory limit"
Apr 28 15:58:42 play dockerd[2738]: time="2018-04-28T15:58:42.624288015Z" level=warning msg="Your kernel does not support cgroup rt period"
Apr 28 15:58:42 play dockerd[2738]: time="2018-04-28T15:58:42.624482225Z" level=warning msg="Your kernel does not support cgroup rt runtime"
Apr 28 15:58:42 play dockerd[2738]: time="2018-04-28T15:58:42.628971087Z" level=info msg="Loading containers: start."
Apr 28 15:59:18 play dockerd[2738]: time="2018-04-28T15:59:18.414916510Z" level=error msg="containerd did not exit successfully" error="signal: killed" module=libcontainerd
Apr 28 15:59:18 play dockerd[2738]: time="2018-04-28T15:59:18.519899178Z" level=error msg="failed to get event" error="rpc error: code = Internal desc = transport is closing" module=libcontainerd namespace=plugins.moby
Apr 28 15:59:18 play dockerd[2738]: time="2018-04-28T15:59:18.535433425Z" level=error msg="failed to get event" error="rpc error: code = Internal desc = transport is closing" module=libcontainerd namespace=moby
Apr 28 15:59:19 play dockerd[2738]: time="2018-04-28T15:59:19.126405882Z" level=info msg="libcontainerd: started new docker-containerd process" pid=2768
Apr 28 15:59:21 play dockerd[2738]: time="2018-04-28T15:59:21.578790869Z" level=error msg="containerd did not exit successfully" error="signal: killed" module=libcontainerd

is there a way to troubleshoot this issue?
I don't really have much other information about how / why it died - or know how to get at that data