<p>Some time ago I asked about handling thousands of services in a Kubernetes cluster:</p>

<p><a href="https://stackoverflow.com/questions/27638334/can-kubernetes-handle-thousands-of-services">Can Kubernetes handle thousands of services?</a></p>

<p>At that time Kubernetes was using env vars and my question was more oriented to that. Now that Kubernetes has a DNS sounds like we don't have the problem with env vars anymore, however the docs still says it won't perform well when handling thousands of services:</p>

<p><a href="https://github.com/GoogleCloudPlatform/kubernetes/blob/master/docs/services.md#shortcomings" rel="nofollow noreferrer">https://github.com/GoogleCloudPlatform/kubernetes/blob/master/docs/services.md#shortcomings</a></p>

<p>Wanted to know if documentation is outdated or if there are still issues to scale Kubernetes to thousands of services.</p>

<p>The shortcoming mentioned in the documentation has not changed, because Kubernetes still uses the same mechanism (iptables and a userspace proxy) for proxying traffic sent to a service IP to the pods backing the service.</p>

<p>However, I don't believe we actually know how bad it is. A team member briefly tried testing it early this year and <a href="https://github.com/GoogleCloudPlatform/kubernetes/issues/3345#issuecomment-69290242" rel="nofollow">didn't see any impact</a>, but didn't do anything rigorous to verify. It's possible that it'll work fine at a couple thousand services. If you try it, we'd love to hear how it goes <a href="https://github.com/GoogleCloudPlatform/kubernetes#community-discussion-and-support" rel="nofollow">via IRC or email</a>.</p>
