title: Worker dyno goes to sleep / idle - Heroku Free tier
body: <p>A Heroku WORKER Dyno (running in a python environment) goes to sleep after 30 mins.
  The worker executes a Celery Period task schedule to send emails to users.</p>
  <p>Here the log showing the actual behaviour&quot;:</p>
  <pre><code>2019-05-29T12:49:02.273852+00:00 heroku[web.1]: Idling
  2019-05-29T12:49:02.278946+00:00 heroku[web.1]: State changed from up to down
  2019-05-29T12:49:02.288616+00:00 heroku[worker.1]: Idling
  2019-05-29T12:49:02.306209+00:00 heroku[worker.1]: State changed from up to down
  2019-05-29T12:49:03.087205+00:00 heroku[worker.1]: Stopping all processes with SIGTERM
  2019-05-29T12:49:03.101608+00:00 app[worker.1]:
  2019-05-29T12:49:03.101688+00:00 app[worker.1]: worker: Warm shutdown (MainProcess)
  2019-05-29T12:49:03.185191+00:00 app[worker.1]: [2019-05-29 12:49:03,184: INFO/MainProcess] beat: Shutting down...
  2019-05-29T12:49:03.297659+00:00 heroku[web.1]: Stopping all processes with SIGTERM
  2019-05-29T12:49:03.324661+00:00 app[web.1]: [2019-05-29 12:49:03 +0000] [4] [INFO] Handling signal: term
  2019-05-29T12:49:03.326185+00:00 app[web.1]: [2019-05-29 12:49:03 +0000] [11] [INFO] Worker exiting (pid: 11)
  2019-05-29T12:49:03.326993+00:00 app[web.1]: [2019-05-29 12:49:03 +0000] [10] [INFO] Worker exiting (pid: 10)
  2019-05-29T12:49:03.626898+00:00 app[web.1]: [2019-05-29 12:49:03 +0000] [4] [INFO] Shutting down: Master
  2019-05-29T12:49:03.758456+00:00 heroku[web.1]: Process exited with status 0
  2019-05-29T12:49:04.817520+00:00 heroku[worker.1]: Process exited with status 0
  </code></pre>
  <p>As per research, I was of the understanding that the <code>web</code> dyno goes to sleep, but the <code>worker</code> dyno will not sleep.
  <a href="https://devcenter.heroku.com/articles/free-dyno-hours" rel="noreferrer">https://devcenter.heroku.com/articles/free-dyno-hours</a> :</p>
  <p>Web:</p>
  <blockquote>
  <p>If an app has a free web dyno, and that dyno receives no web traffic in a 30-minute period, it will sleep.</p>
  <blockquote>
  <p>Warning NOTE: Worker dynos do not sleep, because they do not respond to web requests. Be mindful of this as they may run 24/7 and consume from your pool of hours.</p>
  </blockquote>
  </blockquote>
  <p>I was expecting to have web on idle (av. 250 hours) + full 24/7 of the worker running Celery beat (750 hours) , to stay mainly withing the plan.</p>
  <p>So far I have activated: <a href="https://uptimerobot.com/" rel="noreferrer">https://uptimerobot.com/</a> with an period 5 minutes ping to the web dyno keep it running, but hours won't suffice for a full month. With this both dynos appear to stay awake.</p>
  <p>Any ideas why this is happening?
  Potential solutions?</p>