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vacuum_max_eager_freeze_failure_rateConfigurationReferencevacuum_max_eager_freeze_failure_rate Vacuuming 18 Specifies the maximum number of pages (as a fraction of total pages in the relation) that VACUUM may scan and fail to set all-frozen in the …Configuration · Vacuuming vacuum_multixact_failsafe_ageConfigurationReferencevacuum_multixact_failsafe_age Vacuuming 14 Specifies the maximum age (in multixacts) that a table's pg_class.relminmxid field can attain before VACUUM takes extraordinary measures to avoid s…Configuration · Vacuuming vacuum_multixact_freeze_min_ageConfigurationReferencevacuum_multixact_freeze_min_age Vacuuming 10 Specifies the cutoff age (in multixacts) that VACUUM should use to decide whether to replace multixact IDs with a newer transaction ID or multixa…Configuration · Vacuuming vacuum_multixact_freeze_table_ageConfigurationReferencevacuum_multixact_freeze_table_age Vacuuming 10 VACUUM performs an aggressive scan if the table's pg_class.relminmxid field has reached the age specified by this setting. An aggressive scan d…Configuration · Vacuuming vacuum_truncateConfigurationReferencevacuum_truncate Vacuuming 18 Enables or disables vacuum to try to truncate off any empty pages at the end of the table. The default value is true. If true, VACUUM and autovacuum do the trunc…Configuration · Vacuuming wal_block_sizeConfigurationReferencewal_block_size Preset Options 10 Reports the size of a WAL disk block. It is determined by the value of XLOG_BLCKSZ when building the server. The default value is 8192 bytes. 11 12 13 14 15 …Configuration · Preset Options wal_buffersConfigurationReferencewal_buffers Write-Ahead Log 10 The amount of shared memory used for WAL data that has not yet been written to disk. The default setting of -1 selects a size equal to 1/32nd (about 3%) of sha…Configuration · Write-Ahead Log wal_compressionConfigurationReferencewal_compression Write-Ahead Log 10 When this parameter is on, the PostgreSQL server compresses a full page image written to WAL when full_page_writes is on or during a base backup. A compres…Configuration · Write-Ahead Log wal_consistency_checkingConfigurationReferencewal_consistency_checking Developer Options 10 This parameter is intended to be used to check for bugs in the WAL redo routines. When enabled, full-page images of any buffers modified in conj…Configuration · Developer Options wal_debugConfigurationReferencewal_debug Developer Options 10 If on, emit WAL-related debugging output. This parameter is only available if the WAL_DEBUG macro was defined when PostgreSQL was compiled. 11 12 13 14 15 16 1…Configuration · Developer Options wal_decode_buffer_sizeConfigurationReferencewal_decode_buffer_size Write-Ahead Log 15 A limit on how far ahead the server can look in the WAL, to find blocks to prefetch. If this value is specified without units, it is taken as bytes.…Configuration · Write-Ahead Log wal_init_zeroConfigurationReferencewal_init_zero Write-Ahead Log 12 If set to on (the default), this option causes new WAL files to be filled with zeroes. On some file systems, this ensures that space is allocated before we n…Configuration · Write-Ahead Log wal_keep_segmentsConfigurationReferencewal_keep_segments Replication 10 Specifies the minimum number of past log file segments kept in the pg_wal directory, in case a standby server needs to fetch them for streaming replication. …Configuration · Replication wal_keep_sizeConfigurationReferencewal_keep_size Replication 13 Specifies the minimum size of past log file segments kept in the pg_wal directory, in case a standby server needs to fetch them for streaming replication. If a s…Configuration · Replication wal_log_hintsConfigurationReferencewal_log_hints Write-Ahead Log 10 When this parameter is on, the PostgreSQL server writes the entire content of each disk page to WAL during the first modification of that page after a checkp…Configuration · Write-Ahead Log wal_receiver_create_temp_slotConfigurationReferencewal_receiver_create_temp_slot Replication 13 Specifies whether the WAL receiver process should create a temporary replication slot on the remote instance when no permanent replication slot t…Configuration · Replication wal_receiver_status_intervalConfigurationReferencewal_receiver_status_interval Replication 10 Specifies the minimum frequency for the WAL receiver process on the standby to send information about replication progress to the primary or upstr…Configuration · Replication wal_receiver_timeoutConfigurationReferencewal_receiver_timeout Replication 10 Terminate replication connections that are inactive longer than the specified number of milliseconds. This is useful for the receiving standby server to d…Configuration · Replication wal_recycleConfigurationReferencewal_recycle Write-Ahead Log 12 If set to on (the default), this option causes WAL files to be recycled by renaming them, avoiding the need to create new ones. On COW file systems, it may be …Configuration · Write-Ahead Log wal_retrieve_retry_intervalConfigurationReferencewal_retrieve_retry_interval Replication 10 Specify how long the standby server should wait when WAL data is not available from any sources (streaming replication, local pg_wal or WAL archive…Configuration · Replication wal_segment_sizeConfigurationReferencewal_segment_size Preset Options 10 Reports the number of blocks (pages) in a WAL segment file. The total size of a WAL segment file in bytes is equal to wal_segment_size multiplied by wal_bl…Configuration · Preset Options wal_sender_delayConfigurationReferencewal_sender_delay Replication 9.0 Specifies the delay between activity rounds for WAL sender processes. In each round the WAL sender sends any WAL accumulated since the last round to the stan…Configuration · Replication wal_sender_shutdown_timeoutConfigurationReferencewal_sender_shutdown_timeout Replication 19 Specifies the maximum time the server waits during shutdown for all WAL data to be replicated to the receiver. If this value is specified without u…Configuration · Replication wal_sender_timeoutConfigurationReferencewal_sender_timeout Replication 10 Terminate replication connections that are inactive longer than the specified number of milliseconds. This is useful for the sending server to detect a stan…Configuration · Replication wal_skip_thresholdConfigurationReferencewal_skip_threshold Write-Ahead Log 13 When wal_level is minimal and a transaction commits after creating or rewriting a permanent relation, this setting determines how to persist the new dat…Configuration · Write-Ahead Log wal_summary_keep_timeConfigurationReferencewal_summary_keep_time Write-Ahead Log 17 Configures the amount of time after which the WAL summarizer automatically removes old WAL summaries. The file timestamp is used to determine which f…Configuration · Write-Ahead Log wal_sync_methodConfigurationReferencewal_sync_method Write-Ahead Log 10 Method used for forcing WAL updates out to disk. If fsync is off then this setting is irrelevant, since WAL file updates will not be forced out at all. Pos…Configuration · Write-Ahead Log wal_writer_delayConfigurationReferencewal_writer_delay Write-Ahead Log 10 Specifies how often the WAL writer flushes WAL. After flushing WAL it sleeps for wal_writer_delay milliseconds, unless woken up by an asynchronously commi…Configuration · Write-Ahead Log wal_writer_flush_afterConfigurationReferencewal_writer_flush_after Write-Ahead Log 10 Specifies how often the WAL writer flushes WAL. If the last flush happened less than wal_writer_delay milliseconds ago and less than wal_writer_flus…Configuration · Write-Ahead Log xmlbinaryConfigurationReferencexmlbinary Client Connection Defaults 10 Sets how binary values are to be encoded in XML. This applies for example when bytea values are converted to XML by the functions xmlelement or xmlfor…Configuration · Client Connection Defaults xmloptionConfigurationReferencexmloption Client Connection Defaults 10 Sets whether DOCUMENT or CONTENT is implicit when converting between XML and character string values. See Section 8.13 for a description of this. Vali…Configuration · Client Connection Defaults zero_damaged_pagesConfigurationReferencezero_damaged_pages Developer Options 10 Detection of a damaged page header normally causes PostgreSQL to report an error, aborting the current transaction. Setting zero_damaged_pages to on c…Configuration · Developer Options