How big should a Postgres table be?
The basic block size can be increased when PostgreSQL is built, up to a maximum of 32KB, thereby giving a theoretical table size limit of 64TB. Some operating systems impose a file size limit that prevent files of this size from being created, so PostgreSQL stores table data in multiple files, each 1GB in size.
What’s the default auto vacuum threshold in PostgreSQL?
Specifies a fraction of the table size to add to autovacuum_vacuum_insert_threshold when deciding whether to trigger a VACUUM. The default is 0.2 (20% of table size). This parameter can only be set in the postgresql.conf file or on the server command line; but the setting can be overridden for individual tables by changing table storage parameters.
Is there a way to disable autovacuuming in PostgreSQL?
This parameter can only be set in the postgresql.conf file or on the server command line; however, autovacuuming can be disabled for individual tables by changing table storage parameters. Note that even when this parameter is disabled, the system will launch autovacuum processes if necessary to prevent transaction ID wraparound.
How many tuples do you need to trigger vacuum in PostgreSQL?
Specifies the minimum number of updated or deleted tuples needed to trigger a VACUUM in any one table. The default is 50 tuples. This parameter can only be set in the postgresql.conf file or on the server command line; but the setting can be overridden for individual tables by changing table storage parameters.
Why do I need to vacuum my PostgreSQL table?
VACUUM reclaims storage occupied by dead tuples. In normal PostgreSQL operation, tuples that are deleted or obsoleted by an update are not physically removed from their table; they remain present until a VACUUM is done. Therefore it’s necessary to do VACUUM periodically, especially on frequently-updated tables.