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shared_buffersConfigurationReferenceshared_buffers Resource Usage 10 Sets the amount of memory the database server uses for shared memory buffers. The default is typically 128 megabytes (128MB), but might be less if your kerne…Configuration · Resource Usage wal_levelConfigurationReferencewal_level Write-Ahead Log 10 wal_level determines how much information is written to the WAL. The default value is replica, which writes enough data to support WAL archiving and replication,…Configuration · Write-Ahead Log work_memConfigurationReferencework_mem Resource Usage 10 Specifies the amount of memory to be used by internal sort operations and hash tables before writing to temporary disk files. The value defaults to four megabytes …Configuration · Resource Usage allow_alter_systemConfigurationReferenceallow_alter_system Version and Platform Compatibility 17 When allow_alter_system is set to off, an error is returned if the ALTER SYSTEM command is executed. This parameter can only be set i…Configuration · Version and Platform Compatibility allow_in_place_tablespacesConfigurationReferenceallow_in_place_tablespaces Developer Options 10 Allows tablespaces to be created as directories inside pg_tblspc, when an empty location string is provided to the CREATE TABLESPACE command. …Configuration · Developer Options allow_system_table_modsConfigurationReferenceallow_system_table_mods Developer Options 10 Allows modification of the structure of system tables. This is used by initdb. This parameter can only be set at server start. 11 12 13 Allows mo…Configuration · Developer Options application_nameConfigurationReferenceapplication_name Reporting and Logging 10 The application_name can be any string of less than NAMEDATALEN characters (64 characters in a standard build). It is typically set by an applicatio…Configuration · Reporting and Logging archive_cleanup_commandConfigurationReferencearchive_cleanup_command Write-Ahead Log 12 This optional parameter specifies a shell command that will be executed at every restartpoint. The purpose of archive_cleanup_command is to provide…Configuration · Write-Ahead Log archive_commandConfigurationReferencearchive_command Write-Ahead Log 10 The local shell command to execute to archive a completed WAL file segment. Any %p in the string is replaced by the path name of the file to archive, and a…Configuration · Write-Ahead Log archive_libraryConfigurationReferencearchive_library Write-Ahead Log 15 The library to use for archiving completed WAL file segments. If set to an empty string (the default), archiving via shell is enabled, and archive_command …Configuration · Write-Ahead Log archive_modeConfigurationReferencearchive_mode Write-Ahead Log 10 When archive_mode is enabled, completed WAL segments are sent to archive storage by setting archive_command. In addition to off, to disable, there are two mod…Configuration · Write-Ahead Log archive_timeoutConfigurationReferencearchive_timeout Write-Ahead Log 10 The archive_command is only invoked for completed WAL segments. Hence, if your server generates little WAL traffic (or has slack periods where it does so),…Configuration · Write-Ahead Log array_nullsConfigurationReferencearray_nulls Version and Platform Compatibility 10 This controls whether the array input parser recognizes unquoted NULL as specifying a null array element. By default, this is on, allowing a…Configuration · Version and Platform Compatibility authentication_timeoutConfigurationReferenceauthentication_timeout Connections and Authentication 10 Maximum time to complete client authentication, in seconds. If a would-be client has not completed the authentication protocol in thi…Configuration · Connections and Authentication autovacuumConfigurationReferenceautovacuum Vacuuming 10 Controls whether the server should run the autovacuum launcher daemon. This is on by default; however, track_counts must also be enabled for autovacuum to work. This …Configuration · Vacuuming autovacuum_analyze_scale_factorConfigurationReferenceautovacuum_analyze_scale_factor Vacuuming 10 Specifies a fraction of the table size to add to autovacuum_analyze_threshold when deciding whether to trigger an ANALYZE. The default is 0.1 (10…Configuration · Vacuuming autovacuum_analyze_score_weightConfigurationReferenceautovacuum_analyze_score_weight Vacuuming 19 Specifies the scaling factor of the analyze threshold component of the score used by autovacuum for prioritization purposes. The default is 1.0. …Configuration · Vacuuming autovacuum_analyze_thresholdConfigurationReferenceautovacuum_analyze_threshold Vacuuming 10 Specifies the minimum number of inserted, updated or deleted tuples needed to trigger an ANALYZE in any one table. The default is 50 tuples. This pa…Configuration · Vacuuming autovacuum_freeze_max_ageConfigurationReferenceautovacuum_freeze_max_age Vacuuming 10 Specifies the maximum age (in transactions) that a table's pg_class.relfrozenxid field can attain before a VACUUM operation is forced to prevent transa…Configuration · Vacuuming autovacuum_freeze_score_weightConfigurationReferenceautovacuum_freeze_score_weight Vacuuming 19 Specifies the scaling factor of the transaction ID age component of the score used by autovacuum for prioritization purposes. The default is 1.0. …Configuration · Vacuuming autovacuum_max_parallel_workersConfigurationReferenceautovacuum_max_parallel_workers Vacuuming 19 Sets the maximum number of parallel workers that can be used by a single autovacuum worker to process indexes. This limit applies specifically to…Configuration · Vacuuming autovacuum_max_workersConfigurationReferenceautovacuum_max_workers Vacuuming 10 Specifies the maximum number of autovacuum processes (other than the autovacuum launcher) that may be running at any one time. The default is three. This …Configuration · Vacuuming autovacuum_multixact_freeze_max_ageConfigurationReferenceautovacuum_multixact_freeze_max_age Vacuuming 10 Specifies the maximum age (in multixacts) that a table's pg_class.relminmxid field can attain before a VACUUM operation is forced to prevent …Configuration · Vacuuming autovacuum_multixact_freeze_score_weightConfigurationReferenceautovacuum_multixact_freeze_score_weight Vacuuming 19 Specifies the scaling factor of the multixact ID age component of the score used by autovacuum for prioritization purposes. The default …Configuration · Vacuuming autovacuum_naptimeConfigurationReferenceautovacuum_naptime Vacuuming 10 Specifies the minimum delay between autovacuum runs on any given database. In each round the daemon examines the database and issues VACUUM and ANALYZE comman…Configuration · Vacuuming autovacuum_vacuum_cost_delayConfigurationReferenceautovacuum_vacuum_cost_delay Vacuuming 10 Specifies the cost delay value that will be used in automatic VACUUM operations. If -1 is specified, the regular vacuum_cost_delay value will be use…Configuration · Vacuuming autovacuum_vacuum_cost_limitConfigurationReferenceautovacuum_vacuum_cost_limit Vacuuming 10 Specifies the cost limit value that will be used in automatic VACUUM operations. If -1 is specified (which is the default), the regular vacuum_cost_…Configuration · Vacuuming autovacuum_vacuum_insert_scale_factorConfigurationReferenceautovacuum_vacuum_insert_scale_factor Vacuuming 13 Specifies a fraction of the table size to add to autovacuum_vacuum_insert_threshold when deciding whether to trigger a VACUUM. The default …Configuration · Vacuuming autovacuum_vacuum_insert_score_weightConfigurationReferenceautovacuum_vacuum_insert_score_weight Vacuuming 19 Specifies the scaling factor of the vacuum insert threshold component of the score used by autovacuum for prioritization purposes. The defa…Configuration · Vacuuming autovacuum_vacuum_insert_thresholdConfigurationReferenceautovacuum_vacuum_insert_threshold Vacuuming 13 Specifies the number of inserted tuples needed to trigger a VACUUM in any one table. The default is 1000 tuples. If -1 is specified, autovacuu…Configuration · Vacuuming autovacuum_vacuum_max_thresholdConfigurationReferenceautovacuum_vacuum_max_threshold Vacuuming 18 Specifies the maximum number of updated or deleted tuples needed to trigger a VACUUM in any one table, i.e., a limit on the value calculated with…Configuration · Vacuuming autovacuum_vacuum_scale_factorConfigurationReferenceautovacuum_vacuum_scale_factor Vacuuming 10 Specifies a fraction of the table size to add to autovacuum_vacuum_threshold when deciding whether to trigger a VACUUM. The default is 0.2 (20% of…Configuration · Vacuuming autovacuum_vacuum_score_weightConfigurationReferenceautovacuum_vacuum_score_weight Vacuuming 19 Specifies the scaling factor of the vacuum threshold component of the score used by autovacuum for prioritization purposes. The default is 1.0. Th…Configuration · Vacuuming autovacuum_vacuum_thresholdConfigurationReferenceautovacuum_vacuum_threshold Vacuuming 10 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 o…Configuration · Vacuuming autovacuum_work_memConfigurationReferenceautovacuum_work_mem Resource Usage 10 Specifies the maximum amount of memory to be used by each autovacuum worker process. It defaults to -1, indicating that the value of maintenance_work_me…Configuration · Resource Usage autovacuum_worker_slotsConfigurationReferenceautovacuum_worker_slots Vacuuming 18 Specifies the number of backend slots to reserve for autovacuum worker processes. The default is typically 16 slots, but might be less if your kernel set…Configuration · Vacuuming backend_flush_afterConfigurationReferencebackend_flush_after Resource Usage 10 Whenever more than backend_flush_after bytes have been written by a single backend, attempt to force the OS to issue these writes to the underlying stor…Configuration · Resource Usage backslash_quoteConfigurationReferencebackslash_quote Version and Platform Compatibility 10 This controls whether a quote mark can be represented by \' in a string literal. The preferred, SQL-standard way to represent a quote ma…Configuration · Version and Platform Compatibility backtrace_functionsConfigurationReferencebacktrace_functions Developer Options 13 This parameter contains a comma-separated list of C function names. If an error is raised and the name of the internal C function where the error hap…Configuration · Developer Options bgwriter_delayConfigurationReferencebgwriter_delay Resource Usage 10 Specifies the delay between activity rounds for the background writer. In each round the writer issues writes for some number of dirty buffers (controllable …Configuration · Resource Usage