Missing Sidekiq cluster setup documentation

Problem to solve

Several GitLab suggested architectures presented in our documentation are recommending to run extra Sidekiq nodes to improve performance. However, our documentation does not provide details about how to run this component outside of an application node.

Further details

In the gitlab.rb template is mentioned sidekiq_cluster['enable'] and sidekiq_cluster['ha'] but these options are also not documented in our Sidekiq documentation.

Proposal

We should extend our HA documentation approaching how to setup extra sidekiq nodes, probably the documentation about how to setup extra sidekiq nodes could be linked to it.

• Docs on a single Sidekiq machine !25486 (merged)
• Docs for Sidekiq cluster

Who can address the issue

Someone with knowledge on GitLab HA and especially knowledge on Sidekiq / Sidekiq cluster

Other links/references