数据库数据目录下 base 文件夹有很多 1GB 大小文件，占用几百 G 空间

> 1GB 大小文件

这是 pgsql 的一个文件分片机制： https://www.postgresql.org/docs/current/storage-file-layout.html
> When a table or index exceeds 1 GB, it is divided into gigabyte-sized segments. The first segment's file name is the same as the filenode; subsequent segments are named filenode.1, filenode.2, etc. This arrangement avoids problems on platforms that have file size limitations. (Actually, 1 GB is just the default segment size. The segment size can be adjusted using the configuration option --with-segsize when building PostgreSQL.) In principle, free space map and visibility map forks could require multiple segments as well, though this is unlikely to happen in practice.

根据
https://dba.stackexchange.com/questions/48273/whats-stored-in-data-dir-base-of-postgresql
https://dba.stackexchange.com/questions/228114/why-is-my-postgres-base-directory-filling-up-rapidly
您有执行过[VACUUM]( https://www.postgresql.org/docs/current/routine-vacuuming.html#VACUUM-FOR-SPACE-RECOVERY)吗

@h0099 第一次知道 PostgreSQL 的 VACUUM ，没有执行过。🥲

vacuum full xx 表
会锁表。

pg_repack 或者类似的工具了解一下