Align Elasticsearch Docs with Scalability Docs
Currently users will arrive upon conflicting information regarding the configuration of GitLab.
Specifically, our scalability doc page (which is great by the way) includes no mention whatsoever of Elasticsearch. Specifically, it ought to include mention of:
Elasticsearch should be installed on a separate server, whether you install it yourself or use a cloud hosted offering like Elastic’s Elasticsearch Service (available on AWS, GCP, or Azure) or the Amazon Elasticsearch service. Running Elasticsearch on the same server as GitLab is not recommended and will likely cause a degradation in GitLab instance performance.
(source)
Additionally, the same thing could be said regarding setting up a GitLab Runner which the runner docs discourage GitLab Runners from being on the main GitLab Instance host.
We strongly advise against installing GitLab Runner on the same machine you plan to install GitLab on. Depending on how you decide to configure GitLab Runner and what tools you use to exercise your application in the CI environment, GitLab Runner can consume significant amount of available memory.