Add documentation about sidechannels
Part of gitlab-com/gl-infra&463 (closed) and gitlab-com/gl-infra/scalability#1170 (closed).
This adds high-level documentation about what sidechannel is, why it's there and how it works.
Edited by Jacob Vosmaer
Part of gitlab-com/gl-infra&463 (closed) and gitlab-com/gl-infra/scalability#1170 (closed).
This adds high-level documentation about what sidechannel is, why it's there and how it works.