We currently don't have any consistent way to make use of our standby for read-only queries. This ticket proposes adding a read-only (RO) database connector to MusicBrainz Server which may be used in the web service, or for the website for logged-out users. (It was determined that we shouldn't subject logged-in users to any potential replication lag while editing.)

Initially, this RO connector will only be used for Data::Role::QueryToList. (That actually constitutes a good amount of traffic, as it's used extensively for fetching lists of all types of entities.)

In addition, some background tasks executed by our hourly or daily cron jobs send heavy read-only queries to the primary Postgres server, regularly putting a high load on it and slowing down the rest as a side-effect. Instead, these queries should use the RO connector where possible.