A server parameter determining the maximum number of simultaneous prepared transactions

max_prepared_transactions is a configuration parameter determining the maximum number of prepared transactions which can exist simultaneously.

max_prepared_transactions was added in PostgreSQL 8.1.

Default value

The default value for max_prepared_transactions is: 0.


On a standby, max_prepared_transactions must be set to the same or higher value as on the primary.

The documentation recommends setting max_prepared_transactions to be at least as large as max_connections, though this is not mandatory.

The current value of max_prepared_transactions is one of the configuration parameters recorded in pg_control.

Change history


Critical standby configuration item, GUC configuration item, Memory, Transactions

See also

PREPARE TRANSACTION, pg_prepared_xacts, max_connections