9705: Add docker-cleaner unit file to Install Guide.

diff --git a/doc/_includes/_install_docker_cleaner.liquid b/doc/_includes/_install_docker_cleaner.liquid
index e26b2be586308a2e69d80ab76f415b0671815bef..5671a54ad58b2ae21e8443a683d2677224df6deb 100644 (file)
--- a/doc/_includes/_install_docker_cleaner.liquid
+++ b/doc/_includes/_install_docker_cleaner.liquid
@@ -6,34 +6,36 @@ The arvados-docker-cleaner program removes least recently used Docker images as
 This also removes all containers as soon as they exit, as if they were run with @docker run --rm@. If you need to debug or inspect containers after they stop, temporarily stop arvados-docker-cleaner or run it with @--remove-stopped-containers never@.
 {% include 'notebox_end' %}
 
-Install runit to supervise the Docker cleaner daemon.  {% include 'install_runit' %}
-
-Configure runit to run the image cleaner using a suitable quota for your compute nodes and workload:
+Create a file @/etc/systemd/system/arvados-docker-cleaner.service@ in an editor.  Include the text below as its contents.  Make sure to edit the @ExecStart@ line appropriately for your compute node.
 
 <notextile>
-<pre><code>~$ <span class="userinput">sudo mkdir -p /etc/sv</span>
-~$ <span class="userinput">cd /etc/sv</span>
-/etc/sv$ <span class="userinput">sudo mkdir arvados-docker-cleaner; cd arvados-docker-cleaner</span>
-/etc/sv/arvados-docker-cleaner$ <span class="userinput">sudo mkdir log log/main</span>
-/etc/sv/arvados-docker-cleaner$ <span class="userinput">sudo sh -c 'cat &gt;log/run' &lt;&lt;'EOF'
-#!/bin/sh
-exec svlogd -tt main
-EOF</span>
-/etc/sv/arvados-docker-cleaner$ <span class="userinput">sudo sh -c 'cat &gt;run' &lt;&lt;'EOF'
-#!/bin/sh
-if [ -d /opt/rh/python33 ]; then
-  source scl_source enable python33
-fi
-exec python3 -m arvados_docker.cleaner --quota <b>50G</b>
-EOF</span>
-/etc/sv/arvados-docker-cleaner$ <span class="userinput">sudo chmod +x run log/run</span>
-/etc/sv/arvados-docker-cleaner$ <span class="userinput">sudo ln -s "$(pwd)" /etc/service/</span>
+<pre><code>[Service]
+# Most deployments will want a quota that's at least 10G.  From there,
+# a larger quota can help reduce compute overhead by preventing reloading
+# the same Docker image repeatedly, but will leave less space for other
+# files on the same storage (usually Docker volumes).  Make sure the quota
+# is less than the total space available for Docker images.
+# If your deployment uses a Python 3 Software Collection, uncomment the
+# ExecStart line below, and delete the following one:
+# ExecStart=scl enable python33 "python3 -m arvados_docker.cleaner --quota <span class="userinput">20G</span>"
+ExecStart=python3 -m arvados_docker.cleaner --quota <span class="userinput">20G</span>
+Restart=always
+RestartPreventExitStatus=2
+
+[Install]
+WantedBy=default.target
+
+[Unit]
+After=docker.service
 </code></pre>
 </notextile>
 
-If you are using a different daemon supervisor, or if you want to test the daemon in a terminal window, an equivalent shell command to run arvados-docker-cleaner is:
+Then enable and start the service:
 
 <notextile>
-<pre><code><span class="userinput">python3 -m arvados_docker.cleaner --quota <b>50G</b></span>
+<pre><code>~$ <span class="userinput">sudo systemctl enable arvados-docker-cleaner.service</span>
+~$ <span class="userinput">sudo systemctl start arvados-docker-cleaner.service</span>
 </code></pre>
 </notextile>
+
+If you are using a different daemon supervisor, or if you want to test the daemon in a terminal window, use the command on the @ExecStart@ line above.