Vacuum

https://confluence.atlassian.com/kb/optimize-and-improve-postgresql-performance-with-vacuum-analyze-and-reindex-885239781.html

SELECT name, setting FROM pg_settings WHERE name ILIKE '%autovacuum%';

https://andreigridnev.medium.com/db-maintenance-commands-in-postgresql-analyze-reindex-vacuum-4a14d75bee6c

 running VACUUM ANALYZE and then REINDEX commands on the biggest tables in the application database really helps to improve its performance.

psql mydb

vacuum  analyze verbose

vacuum full analyze verbose

SHOW AUTOVACUUM;

Show bloat

https://wiki.postgresql.org/wiki/Show_database_bloat

Postgres Vacuum

$ docker run --rm -d --name postgres postgres:10.1
6732b0b9c6245fe9f19dd58e9737e5102089814e4aa96b66217af28a1596f786

$ docker exec -it postgres bash

root@6732b0b9c624:/# psql -Upostgres
psql (10.1)
Type "help" for help.

postgres=# CREATE TABLE floor (
postgres(# name text,
postgres(# type text
postgres(# );
CREATE TABLE

postgres=# vacuum floor;
VACUUM

postgres=# SELECT relname, last_vacuum, last_autovacuum FROM pg_stat_user_tables;
 relname |          last_vacuum          | last_autovacuum 
---------+-------------------------------+-----------------
 floor   | 2019-04-24 17:52:26.044697+00 | 
(1 row)