Interesting read, but I find it very lacking. PGSQL memory consists of lots of parts; shared_buffers, work_mem, maintenance_work_men, OS Cache size, etc. For those who are interested in a deeper Postgresql tuning tutorial, I suggest this[1] as it highlights a number of important tuning options - specifically for PGSQL 17. Once your DB has been running for a while, run the postgresql-tuner app[2] to see if you have correctly applied RAM settings[2]. The repo has been around for a long time, but I find the recommendations (especially the estimated RAM usage) really good.

[1] https://www.pgedge.com/blog/postgresql-performance-tuning

[2] https://github.com/jfcoz/postgresqltuner

Beware, the first link appears to be AI slop with at least some bogus information. For example, it says "While PostgreSQL 15 introduced basic WAL compression", but WAL compression has been around since before 15.