why does google appengine deployment take several minutes to update service : <p>I'm using nodejs flexible environment documented <a href="https://cloud.google.com/appengine/docs/flexible/nodejs/configuring-your-app-with-app-yaml" rel="noreferrer">here</a></p>

<p>Nothing fancy in the config</p>

<pre><code>runtime: nodejs
vm: true
service: SimpleExpressService
health_check:
  enable_health_check: False
automatic_scaling:
  min_num_instances: 1
  max_num_instances: 4
  cool_down_period_sec: 120
  cpu_utilization:
    target_utilization: 0.5
</code></pre>

<p>Here is my deployment command</p>

<pre><code>gcloud app deploy -q --promote --version $VER
</code></pre>

<p>Whenever I deploy a new version, almost everything goes really fast. However, the step 'Updating service [SimpleExpressServer]' takes several minutes. </p>

<p>Is there anyway to optimize this step?</p>

<p><a href="https://i.stack.imgur.com/7oUVt.png" rel="noreferrer"><img src="https://i.stack.imgur.com/7oUVt.png" alt="enter image description here"></a></p>
