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Version: 1.0.16

Autovacuum Parameters

autovacuum​

Boolean type. Whether to enable automatic cleanup. Default value on. When enabled, track_counts must also be on.

autovacuum = on            # Enable autovacuum subprocess?  'on'
                            # requires track_counts to also be on.

autovacuum_max_workers​

Numeric type. Maximum number of cleanup worker processes. Default value 3. This parameter can only be set at instance startup.

autovacuum_max_workers = 3        # max number of autovacuum subprocesses
                                    # (change requires restart)

autovacuum_vacuum_threshold​

Numeric type. Minimum number of row updates to trigger cleanup. Default value 50.

autovacuum_vacuum_threshold = 50    # min number of row updates before
                                    # vacuum

autovacuum_vacuum_scale_factor​

Numeric type. Scale factor for triggering cleanup by update (UPDATE) and delete (DELETE) operations. The trigger threshold is determined by the formula autovacuum_vacuum_scale_factor x total table rows + autovacuum_vacuum_threshold. Default value 0.2 (20%).

autovacuum_vacuum_scale_factor = 0.2    # fraction of table size before vacuum

autovacuum_vacuum_insert_threshold​

Numeric type. Minimum number of insert (INSERT) operations to trigger cleanup. Default value 1000. Set to -1 to disable insert cleanup.

autovacuum_vacuum_insert_threshold = 1000    # min number of row inserts
                                            # before vacuum; -1 disables insert
                                            # vacuums

autovacuum_vacuum_insert_scale_factor​

Numeric type. Scale factor for triggering cleanup by insert operations. The trigger threshold is determined by the formula autovacuum_vacuum_insert_scale_factor x total table rows + autovacuum_vacuum_insert_threshold. Default value 0.2 (20%).

autovacuum_vacuum_insert_scale_factor = 0.2    # fraction of inserts over table
                                                # size before insert vacuum

autovacuum_analyze_threshold​

Numeric type. Minimum number of row updates to trigger statistics collection (ANALYZE). Default value 50.

autovacuum_analyze_threshold = 50    # min number of row updates before
                                    # analyze

autovacuum_analyze_scale_factor​

Numeric type. Scale factor for triggering statistics collection (ANALYZE) by insert, update, and delete operations. The trigger threshold is determined by the formula autovacuum_analyze_scale_factor x total table rows + autovacuum_analyze_threshold. Default value 0.1 (10%).

autovacuum_analyze_scale_factor = 0.1    # fraction of table size before analyze

autovacuum_freeze_max_age​

Numeric type. Maximum transaction age allowed on a table. If this value is exceeded, transactions on that table will be forcibly frozen. Default value 200000000. This parameter can only be set at instance startup.

autovacuum_freeze_max_age = 200000000    # maximum XID age before forced vacuum
                                        # (change requires restart)