The default values of some parameters in PolarDB for PostgreSQL are modified from V1.1.28 of PostgreSQL 11 and V14.5.1.1 of PostgreSQL 14.
Background information
The default values of some parameters in PolarDB for PostgreSQL are modified. The modifications are valid only for new clusters. New default values can significantly improve the performance of databases. You can modify the default values in the console.
Note You can execute the following statement to view the minor version of a PolarDB for PostgreSQL cluster:
- PostgreSQL 11
show polar_version;
- PostgreSQL 14
select version();
Parameters
The default values are modified for the following parameters.
Parameter | Default value | Description |
---|---|---|
synchronous_commit | off | Specifies whether a transaction needs to wait for WAL records to be written to the disk before it returns a success message to the client. Default value: off. Valid values:
Note You can execute the following statement to view the settings of this parameter for the current cluster:
|
wal_level | replica | Specifies what types of data are written to WAL. Default value: replica. Valid values: Default value: replica. Valid values:
Warning The cluster restarts after you modify this parameter. Proceed with caution. Note You can execute the following statement to view the settings of this parameter for the current cluster:
|
log_statement | ddl | Specifies the level of audit logs. Default value: ddl, which indicates that only logs for DDL statements are audited. Displaying less logs can improve database performance. Note
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Note For more information about the default values of other parameters, see Default values of cluster parameters.