At minimum, the Instance installer guides and documentation needs to reflect that your own server doing real-time searches should be a conscious choice.
Lemmy.ml is erroring out already on searches, GitHub issue: https://github.com/LemmyNet/lemmy/issues/3296
And if I’m seeing things right, 0.18 changed the loging from 0.17 where searching for a community https://lemmy.ml/communities now does a full-text posting/comment search? It gives a ton of output I don’t want, and it’s hitting the database even harder. Instead of just searching a single database table, now it is going into comments and postings.
Reddit was legendary for not having their own in-build comment and posting search engine up to date - and also used PostgreSQL (at least they did when still open source). It is a huge amount of data and I/O processing.
postgresql has integrated full text search functionality that works pretty well. shouldn’t be too hard to add