| autovacuum
| on | Autovacuum
| sighup
| Starts the autovacuum subprocess.
|
| autovacuum_analyze_scale_factor
| 0.1 | Autovacuum
| sighup
| Number of tuple inserts, updates or deletes prior to analyze as a fraction of reltuples.
|
| autovacuum_analyze_threshold
| 50 | Autovacuum
| sighup
| Minimum number of tuple inserts, updates or deletes prior to analyze.
|
| autovacuum_freeze_max_age
| 200000000 | Autovacuum
| postmaster
| Age at which to autovacuum a table to prevent transaction ID wraparound.
|
| autovacuum_max_workers
| 3 | Autovacuum
| postmaster
| Sets the maximum number of simultaneously running autovacuum worker processes.
|
| autovacuum_naptime
| 60 s | Autovacuum
| sighup
| Time to sleep between autovacuum runs.
|
| autovacuum_vacuum_cost_delay
| 20 ms | Autovacuum
| sighup
| Vacuum cost delay in milliseconds, for autovacuum.
|
| autovacuum_vacuum_cost_limit
| -1 | Autovacuum
| sighup
| Vacuum cost amount available before napping, for autovacuum.
|
| autovacuum_vacuum_scale_factor
| 0.2 | Autovacuum
| sighup
| Number of tuple updates or deletes prior to vacuum as a fraction of reltuples.
|
| autovacuum_vacuum_threshold
| 50 | Autovacuum
| sighup
| Minimum number of tuple updates or deletes prior to vacuum.
|
| client_encoding
| UTF8 | Client Connection Defaults / Locale and Formatting
| user
| Sets the client's character set encoding.
|
| DateStyle
| ISO, MDY | Client Connection Defaults / Locale and Formatting
| user
| Also controls interpretation of ambiguous date inputs.
|
| default_text_search_config
| pg_catalog.english | Client Connection Defaults / Locale and Formatting
| user
| Sets default text search configuration.
|
| extra_float_digits
| 2 | Client Connection Defaults / Locale and Formatting
| user
| This affects real, double precision, and geometric data types. The parameter value is added to the standard number of digits (FLT_DIG or DBL_DIG as appropriate).
|
| lc_collate
| English_United States.1252 | Client Connection Defaults / Locale and Formatting
| internal
| Shows the collation order locale.
|
| lc_ctype
| English_United States.1252 | Client Connection Defaults / Locale and Formatting
| internal
| Shows the character classification and case conversion locale.
|
| lc_messages
| English_United States.1252 | Client Connection Defaults / Locale and Formatting
| superuser
| Sets the language in which messages are displayed.
|
| lc_monetary
| English_United States.1252 | Client Connection Defaults / Locale and Formatting
| user
| Sets the locale for formatting monetary amounts.
|
| lc_numeric
| English_United States.1252 | Client Connection Defaults / Locale and Formatting
| user
| Sets the locale for formatting numbers.
|
| lc_time
| English_United States.1252 | Client Connection Defaults / Locale and Formatting
| user
| Sets the locale for formatting date and time values.
|
| server_encoding
| UTF8 | Client Connection Defaults / Locale and Formatting
| internal
| Sets the server (database) character set encoding.
|
| TimeZone
| US/Pacific | Client Connection Defaults / Locale and Formatting
| user
| Sets the time zone for displaying and interpreting time stamps.
|
| timezone_abbreviations
| Default | Client Connection Defaults / Locale and Formatting
| user
| Selects a file of time zone abbreviations.
|
| dynamic_library_path
| $libdir | Client Connection Defaults / Other Defaults
| superuser
| If a dynamically loadable module needs to be opened and the specified name does not have a directory component (i.e., the name does not contain a slash), the system will search this path for the specified file.
|
| explain_pretty_print
| on | Client Connection Defaults / Other Defaults
| user
| Uses the indented output format for EXPLAIN VERBOSE.
|
| gin_fuzzy_search_limit
| 0 | Client Connection Defaults / Other Defaults
| user
| Sets the maximum allowed result for exact search by GIN.
|
| local_preload_libraries
| | Client Connection Defaults / Other Defaults
| backend
| Lists shared libraries to preload into each backend.
|
| tcp_keepalives_count
| 0 | Client Connection Defaults / Other Defaults
| user
| This controls the number of consecutive keepalive retransmits that can be lost before a connection is considered dead. A value of 0 uses the system default.
|
| tcp_keepalives_idle
| 0 s | Client Connection Defaults / Other Defaults
| user
| A value of 0 uses the system default.
|
| tcp_keepalives_interval
| 0 s | Client Connection Defaults / Other Defaults
| user
| A value of 0 uses the system default.
|
| check_function_bodies
| on | Client Connection Defaults / Statement Behavior
| user
| Check function bodies during CREATE FUNCTION.
|
| default_tablespace
| | Client Connection Defaults / Statement Behavior
| user
| An empty string selects the database's default tablespace.
|
| default_transaction_isolation
| read committed | Client Connection Defaults / Statement Behavior
| user
| Each SQL transaction has an isolation level, which can be either "read uncommitted", "read committed", "repeatable read", or "serializable".
|
| default_transaction_read_only
| off | Client Connection Defaults / Statement Behavior
| user
| Sets the default read-only status of new transactions.
|
| search_path
| "$user",public | Client Connection Defaults / Statement Behavior
| user
| Sets the schema search order for names that are not schema-qualified.
|
| session_replication_role
| origin | Client Connection Defaults / Statement Behavior
| superuser
| Each session can be either "origin", "replica", or "local".
|
| statement_timeout
| 0 ms | Client Connection Defaults / Statement Behavior
| user
| A value of 0 turns off the timeout.
|
| temp_tablespaces
| | Client Connection Defaults / Statement Behavior
| user
| Sets the tablespace(s) to use for temporary tables and sort files.
|
| transaction_isolation
| read committed | Client Connection Defaults / Statement Behavior
| user
| Sets the current transaction's isolation level.
|
| transaction_read_only
| off | Client Connection Defaults / Statement Behavior
| user
| Sets the current transaction's read-only status.
|
| vacuum_freeze_min_age
| 100000000 | Client Connection Defaults / Statement Behavior
| user
| Minimum age at which VACUUM should freeze a table row.
|
| xmlbinary
| base64 | Client Connection Defaults / Statement Behavior
| user
| Valid values are BASE64 and HEX.
|
| xmloption
| content | Client Connection Defaults / Statement Behavior
| user
| Valid values are DOCUMENT and CONTENT.
|
| bonjour_name
| | Connections and Authentication / Connection Settings
| postmaster
| Sets the Bonjour broadcast service name.
|
| listen_addresses
| * | Connections and Authentication / Connection Settings
| postmaster
| Sets the host name or IP address(es) to listen to.
|
| max_connections
| 100 | Connections and Authentication / Connection Settings
| postmaster
| Sets the maximum number of concurrent connections.
|
| port
| 5432 | Connections and Authentication / Connection Settings
| postmaster
| Sets the TCP port the server listens on.
|
| superuser_reserved_connections
| 3 | Connections and Authentication / Connection Settings
| postmaster
| Sets the number of connection slots reserved for superusers.
|
| unix_socket_directory
| | Connections and Authentication / Connection Settings
| postmaster
| Sets the directory where the Unix-domain socket will be created.
|
| unix_socket_group
| | Connections and Authentication / Connection Settings
| postmaster
| The owning user of the socket is always the user that starts the server.
|
| unix_socket_permissions
| 511 | Connections and Authentication / Connection Settings
| postmaster
| Unix-domain sockets use the usual Unix file system permission set. The parameter value is expected to be an numeric mode specification in the form accepted by the chmod and umask system calls. (To use the customary octal format the number must start with a 0 (zero).)
|
| authentication_timeout
| 60 s | Connections and Authentication / Security and Authentication
| sighup
| Sets the maximum allowed time to complete client authentication.
|
| db_user_namespace
| off | Connections and Authentication / Security and Authentication
| sighup
| Enables per-database user names.
|
| krb_caseins_users
| off | Connections and Authentication / Security and Authentication
| postmaster
| Sets whether Kerberos and GSSAPI user names should be treated as case-insensitive.
|
| krb_realm
| | Connections and Authentication / Security and Authentication
| postmaster
| Sets realm to match Kerberos and GSSAPI users against.
|
| krb_server_hostname
| | Connections and Authentication / Security and Authentication
| postmaster
| Sets the hostname of the Kerberos server.
|
| krb_server_keyfile
| | Connections and Authentication / Security and Authentication
| postmaster
| Sets the location of the Kerberos server key file.
|
| krb_srvname
| postgres | Connections and Authentication / Security and Authentication
| postmaster
| Sets the name of the Kerberos service.
|
| password_encryption
| on | Connections and Authentication / Security and Authentication
| user
| When a password is specified in CREATE USER or ALTER USER without writing either ENCRYPTED or UNENCRYPTED, this parameter determines whether the password is to be encrypted.
|
| ssl
| off | Connections and Authentication / Security and Authentication
| postmaster
| Enables SSL connections.
|
| ssl_ciphers
| ALL:!ADH:!LOW:!EXP:!MD5:@STRENGTH | Connections and Authentication / Security and Authentication
| postmaster
| Sets the list of allowed SSL ciphers.
|
| custom_variable_classes
| | Customized Options
| sighup
| Sets the list of known custom variable classes.
|
| allow_system_table_mods
| off | Developer Options
| postmaster
| Allows modifications of the structure of system tables.
|
| debug_assertions
| off | Developer Options
| user
| This is a debugging aid.
|
| ignore_system_indexes
| off | Developer Options
| backend
| It does not prevent updating the indexes, so it is safe to use. The worst consequence is slowness.
|
| post_auth_delay
| 0 s | Developer Options
| backend
| This allows attaching a debugger to the process.
|
| pre_auth_delay
| 0 s | Developer Options
| sighup
| This allows attaching a debugger to the process.
|
| trace_notify
| off | Developer Options
| user
| Generates debugging output for LISTEN and NOTIFY.
|
| trace_sort
| off | Developer Options
| user
| Emit information about resource usage in sorting.
|
| zero_damaged_pages
| off | Developer Options
| superuser
| Detection of a damaged page header normally causes PostgreSQL to report an error, aborting the current transaction. Setting zero_damaged_pages to true causes the system to instead report a warning, zero out the damaged page, and continue processing. This behavior will destroy data, namely all the rows on the damaged page.
|
| config_file
| C:/Program Files/PostgreSQL/8.3/data/postgresql.conf | File Locations
| postmaster
| Sets the server's main configuration file.
|
| data_directory
| C:/Program Files/PostgreSQL/8.3/data | File Locations
| postmaster
| Sets the server's data directory.
|
| external_pid_file
| | File Locations
| postmaster
| Writes the postmaster PID to the specified file.
|
| hba_file
| C:/Program Files/PostgreSQL/8.3/data/pg_hba.conf | File Locations
| postmaster
| Sets the server's "hba" configuration file.
|
| ident_file
| C:/Program Files/PostgreSQL/8.3/data/pg_ident.conf | File Locations
| postmaster
| Sets the server's "ident" configuration file.
|
| deadlock_timeout
| 1000 ms | Lock Management
| sighup
| Sets the time to wait on a lock before checking for deadlock.
|
| max_locks_per_transaction
| 64 | Lock Management
| postmaster
| The shared lock table is sized on the assumption that at most max_locks_per_transaction * max_connections distinct objects will need to be locked at any one time.
|
| block_size
| 8192 | Preset Options
| internal
| Shows the size of a disk block.
|
| integer_datetimes
| on | Preset Options
| internal
| Datetimes are integer based.
|
| max_function_args
| 100 | Preset Options
| internal
| Shows the maximum number of function arguments.
|
| max_identifier_length
| 63 | Preset Options
| internal
| Shows the maximum identifier length.
|
| max_index_keys
| 32 | Preset Options
| internal
| Shows the maximum number of index keys.
|
| server_version
| 8.3.7 | Preset Options
| internal
| Shows the server version.
|
| server_version_num
| 80307 | Preset Options
| internal
| Shows the server version as an integer.
|
| geqo
| on | Query Tuning / Genetic Query Optimizer
| user
| This algorithm attempts to do planning without exhaustive searching.
|
| geqo_effort
| 5 | Query Tuning / Genetic Query Optimizer
| user
| GEQO: effort is used to set the default for other GEQO parameters.
|
| geqo_generations
| 0 | Query Tuning / Genetic Query Optimizer
| user
| Zero selects a suitable default value.
|
| geqo_pool_size
| 0 | Query Tuning / Genetic Query Optimizer
| user
| Zero selects a suitable default value.
|
| geqo_selection_bias
| 2 | Query Tuning / Genetic Query Optimizer
| user
| GEQO: selective pressure within the population.
|
| geqo_threshold
| 12 | Query Tuning / Genetic Query Optimizer
| user
| Sets the threshold of FROM items beyond which GEQO is used.
|
| constraint_exclusion
| off | Query Tuning / Other Planner Options
| user
| Child table scans will be skipped if their constraints guarantee that no rows match the query.
|
| default_statistics_target
| 10 | Query Tuning / Other Planner Options
| user
| This applies to table columns that have not had a column-specific target set via ALTER TABLE SET STATISTICS.
|
| from_collapse_limit
| 8 | Query Tuning / Other Planner Options
| user
| The planner will merge subqueries into upper queries if the resulting FROM list would have no more than this many items.
|
| join_collapse_limit
| 8 | Query Tuning / Other Planner Options
| user
| The planner will flatten explicit JOIN constructs into lists of FROM items whenever a list of no more than this many items would result.
|
| cpu_index_tuple_cost
| 0.005 | Query Tuning / Planner Cost Constants
| user
| Sets the planner's estimate of the cost of processing each index entry during an index scan.
|
| cpu_operator_cost
| 0.0025 | Query Tuning / Planner Cost Constants
| user
| Sets the planner's estimate of the cost of processing each operator or function call.
|
| cpu_tuple_cost
| 0.01 | Query Tuning / Planner Cost Constants
| user
| Sets the planner's estimate of the cost of processing each tuple (row).
|
| effective_cache_size
| 16384 8kB | Query Tuning / Planner Cost Constants
| user
| That is, the portion of the kernel's disk cache that will be used for PostgreSQL data files. This is measured in disk pages, which are normally 8 kB each.
|
| random_page_cost
| 4 | Query Tuning / Planner Cost Constants
| user
| Sets the planner's estimate of the cost of a nonsequentially fetched disk page.
|
| seq_page_cost
| 1 | Query Tuning / Planner Cost Constants
| user
| Sets the planner's estimate of the cost of a sequentially fetched disk page.
|
| enable_bitmapscan
| on | Query Tuning / Planner Method Configuration
| user
| Enables the planner's use of bitmap-scan plans.
|
| enable_hashagg
| on | Query Tuning / Planner Method Configuration
| user
| Enables the planner's use of hashed aggregation plans.
|
| enable_hashjoin
| on | Query Tuning / Planner Method Configuration
| user
| Enables the planner's use of hash join plans.
|
| enable_indexscan
| on | Query Tuning / Planner Method Configuration
| user
| Enables the planner's use of index-scan plans.
|
| enable_mergejoin
| on | Query Tuning / Planner Method Configuration
| user
| Enables the planner's use of merge join plans.
|
| enable_nestloop
| on | Query Tuning / Planner Method Configuration
| user
| Enables the planner's use of nested-loop join plans.
|
| enable_seqscan
| on | Query Tuning / Planner Method Configuration
| user
| Enables the planner's use of sequential-scan plans.
|
| enable_sort
| on | Query Tuning / Planner Method Configuration
| user
| Enables the planner's use of explicit sort steps.
|
| enable_tidscan
| on | Query Tuning / Planner Method Configuration
| user
| Enables the planner's use of TID scan plans.
|
| debug_pretty_print
| off | Reporting and Logging / What to Log
| user
| Indents parse and plan tree displays.
|
| debug_print_parse
| off | Reporting and Logging / What to Log
| user
| Prints the parse tree to the server log.
|
| debug_print_plan
| off | Reporting and Logging / What to Log
| user
| Prints the execution plan to server log.
|
| debug_print_rewritten
| off | Reporting and Logging / What to Log
| user
| Prints the parse tree after rewriting to server log.
|
| log_autovacuum_min_duration
| -1 ms | Reporting and Logging / What to Log
| sighup
| Zero prints all actions. -1 turns autovacuum logging off.
|
| log_checkpoints
| off | Reporting and Logging / What to Log
| sighup
| Logs each checkpoint.
|
| log_connections
| off | Reporting and Logging / What to Log
| backend
| Logs each successful connection.
|
| log_disconnections
| off | Reporting and Logging / What to Log
| backend
| Logs end of a session, including duration.
|
| log_duration
| off | Reporting and Logging / What to Log
| superuser
| Logs the duration of each completed SQL statement.
|
| log_hostname
| off | Reporting and Logging / What to Log
| sighup
| By default, connection logs only show the IP address of the connecting host. If you want them to show the host name you can turn this on, but depending on your host name resolution setup it might impose a non-negligible performance penalty.
|
| log_line_prefix
| %%t | Reporting and Logging / What to Log
| sighup
| If blank, no prefix is used.
|
| log_lock_waits
| off | Reporting and Logging / What to Log
| superuser
| Logs long lock waits.
|
| log_statement
| none | Reporting and Logging / What to Log
| superuser
| Valid values are "none", "ddl", "mod", and "all".
|
| log_temp_files
| -1 kB | Reporting and Logging / What to Log
| user
| Zero logs all files. The default is -1 (turning this feature off).
|
| log_timezone
| US/Pacific | Reporting and Logging / What to Log
| sighup
| Sets the time zone to use in log messages.
|
| client_min_messages
| notice | Reporting and Logging / When to Log
| user
| Valid values are DEBUG5, DEBUG4, DEBUG3, DEBUG2, DEBUG1, LOG, NOTICE, WARNING, and ERROR. Each level includes all the levels that follow it. The later the level, the fewer messages are sent.
|
| log_error_verbosity
| default | Reporting and Logging / When to Log
| superuser
| Valid values are "terse", "default", and "verbose".
|
| log_min_duration_statement
| -1 ms | Reporting and Logging / When to Log
| superuser
| Zero prints all queries. -1 turns this feature off.
|
| log_min_error_statement
| error | Reporting and Logging / When to Log
| superuser
| All SQL statements that cause an error of the specified level or a higher level are logged.
|
| log_min_messages
| notice | Reporting and Logging / When to Log
| superuser
| Valid values are DEBUG5, DEBUG4, DEBUG3, DEBUG2, DEBUG1, INFO, NOTICE, WARNING, ERROR, LOG, FATAL, and PANIC. Each level includes all the levels that follow it.
|
| silent_mode
| off | Reporting and Logging / When to Log
| postmaster
| If this parameter is set, the server will automatically run in the background and any controlling terminals are dissociated.
|
| log_destination
| stderr | Reporting and Logging / Where to Log
| sighup
| Valid values are combinations of "stderr", "syslog", "csvlog", and "eventlog", depending on the platform.
|
| log_directory
| pg_log | Reporting and Logging / Where to Log
| sighup
| Can be specified as relative to the data directory or as absolute path.
|
| log_filename
| postgresql-%Y-%m-%d_%H%M%S.log | Reporting and Logging / Where to Log
| sighup
| Sets the file name pattern for log files.
|
| log_rotation_age
| 1440 min | Reporting and Logging / Where to Log
| sighup
| Automatic log file rotation will occur after N minutes.
|
| log_rotation_size
| 10240 kB | Reporting and Logging / Where to Log
| sighup
| Automatic log file rotation will occur after N kilobytes.
|
| log_truncate_on_rotation
| off | Reporting and Logging / Where to Log
| sighup
| Truncate existing log files of same name during log rotation.
|
| logging_collector
| on | Reporting and Logging / Where to Log
| postmaster
| Start a subprocess to capture stderr output and/or csvlogs into log files.
|
| bgwriter_delay
| 200 ms | Resource Usage
| sighup
| Background writer sleep time between rounds.
|
| bgwriter_lru_maxpages
| 100 | Resource Usage
| sighup
| Background writer maximum number of LRU pages to flush per round.
|
| bgwriter_lru_multiplier
| 2 | Resource Usage
| sighup
| Background writer multiplier on average buffers to scan per round.
|
| max_prepared_transactions
| 5 | Resource Usage
| postmaster
| Sets the maximum number of simultaneously prepared transactions.
|
| vacuum_cost_delay
| 0 ms | Resource Usage
| user
| Vacuum cost delay in milliseconds.
|
| vacuum_cost_limit
| 200 | Resource Usage
| user
| Vacuum cost amount available before napping.
|
| vacuum_cost_page_dirty
| 20 | Resource Usage
| user
| Vacuum cost for a page dirtied by vacuum.
|
| vacuum_cost_page_hit
| 1 | Resource Usage
| user
| Vacuum cost for a page found in the buffer cache.
|
| vacuum_cost_page_miss
| 10 | Resource Usage
| user
| Vacuum cost for a page not found in the buffer cache.
|
| max_fsm_pages
| 204800 | Resource Usage / Free Space Map
| postmaster
| Sets the maximum number of disk pages for which free space is tracked.
|
| max_fsm_relations
| 1000 | Resource Usage / Free Space Map
| postmaster
| Sets the maximum number of tables and indexes for which free space is tracked.
|
| max_files_per_process
| 1000 | Resource Usage / Kernel Resources
| postmaster
| Sets the maximum number of simultaneously open files for each server process.
|
| shared_preload_libraries
| | Resource Usage / Kernel Resources
| postmaster
| Lists shared libraries to preload into server.
|
| maintenance_work_mem
| 16384 kB | Resource Usage / Memory
| user
| This includes operations such as VACUUM and CREATE INDEX.
|
| max_stack_depth
| 2048 kB | Resource Usage / Memory
| superuser
| Sets the maximum stack depth, in kilobytes.
|
| shared_buffers
| 4096 8kB | Resource Usage / Memory
| postmaster
| Sets the number of shared memory buffers used by the server.
|
| temp_buffers
| 1024 8kB | Resource Usage / Memory
| user
| Sets the maximum number of temporary buffers used by each session.
|
| work_mem
| 1024 kB | Resource Usage / Memory
| user
| This much memory can be used by each internal sort operation and hash table before switching to temporary disk files.
|
| log_executor_stats
| off | Statistics / Monitoring
| superuser
| Writes executor performance statistics to the server log.
|
| log_parser_stats
| off | Statistics / Monitoring
| superuser
| Writes parser performance statistics to the server log.
|
| log_planner_stats
| off | Statistics / Monitoring
| superuser
| Writes planner performance statistics to the server log.
|
| log_statement_stats
| off | Statistics / Monitoring
| superuser
| Writes cumulative performance statistics to the server log.
|
| track_activities
| on | Statistics / Query and Index Statistics Collector
| superuser
| Enables the collection of information on the currently executing command of each session, along with the time at which that command began execution.
|
| track_counts
| on | Statistics / Query and Index Statistics Collector
| superuser
| Collects statistics on database activity.
|
| update_process_title
| on | Statistics / Query and Index Statistics Collector
| superuser
| Enables updating of the process title every time a new SQL command is received by the server.
|
| transform_null_equals
| off | Version and Platform Compatibility / Other Platforms and Clients
| user
| When turned on, expressions of the form expr = NULL (or NULL = expr) are treated as expr IS NULL, that is, they return true if expr evaluates to the null value, and false otherwise. The correct behavior of expr = NULL is to always return null (unknown).
|
| add_missing_from
| off | Version and Platform Compatibility / Previous PostgreSQL Versions
| user
| Automatically adds missing table references to FROM clauses.
|
| array_nulls
| on | Version and Platform Compatibility / Previous PostgreSQL Versions
| user
| When turned on, unquoted NULL in an array input value means a null value; otherwise it is taken literally.
|
| backslash_quote
| safe_encoding | Version and Platform Compatibility / Previous PostgreSQL Versions
| user
| Valid values are ON, OFF, and SAFE_ENCODING.
|
| default_with_oids
| off | Version and Platform Compatibility / Previous PostgreSQL Versions
| user
| Create new tables with OIDs by default.
|
| escape_string_warning
| on | Version and Platform Compatibility / Previous PostgreSQL Versions
| user
| Warn about backslash escapes in ordinary string literals.
|
| regex_flavor
| advanced | Version and Platform Compatibility / Previous PostgreSQL Versions
| user
| This can be set to advanced, extended, or basic.
|
| sql_inheritance
| on | Version and Platform Compatibility / Previous PostgreSQL Versions
| user
| Causes subtables to be included by default in various commands.
|
| standard_conforming_strings
| off | Version and Platform Compatibility / Previous PostgreSQL Versions
| user
| Causes '...' strings to treat backslashes literally.
|
| synchronize_seqscans
| on | Version and Platform Compatibility / Previous PostgreSQL Versions
| user
| Enable synchronized sequential scans.
|
| checkpoint_completion_target
| 0.5 | Write-Ahead Log / Checkpoints
| sighup
| Time spent flushing dirty buffers during checkpoint, as fraction of checkpoint interval.
|
| checkpoint_segments
| 3 | Write-Ahead Log / Checkpoints
| sighup
| Sets the maximum distance in log segments between automatic WAL checkpoints.
|
| checkpoint_timeout
| 300 s | Write-Ahead Log / Checkpoints
| sighup
| Sets the maximum time between automatic WAL checkpoints.
|
| checkpoint_warning
| 30 s | Write-Ahead Log / Checkpoints
| sighup
| Write a message to the server log if checkpoints caused by the filling of checkpoint segment files happens more frequently than this number of seconds. Zero turns off the warning.
|
| archive_command
| (disabled) | Write-Ahead Log / Settings
| sighup
| Sets the shell command that will be called to archive a WAL file.
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| archive_mode
| off | Write-Ahead Log / Settings
| postmaster
| Allows archiving of WAL files using archive_command.
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| archive_timeout
| 0 s | Write-Ahead Log / Settings
| sighup
| Forces a switch to the next xlog file if a new file has not been started within N seconds.
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| commit_delay
| 0 | Write-Ahead Log / Settings
| user
| Sets the delay in microseconds between transaction commit and flushing WAL to disk.
|
| commit_siblings
| 5 | Write-Ahead Log / Settings
| user
| Sets the minimum concurrent open transactions before performing commit_delay.
|
| fsync
| on | Write-Ahead Log / Settings
| sighup
| The server will use the fsync() system call in several places to make sure that updates are physically written to disk. This insures that a database cluster will recover to a consistent state after an operating system or hardware crash.
|
| full_page_writes
| on | Write-Ahead Log / Settings
| sighup
| A page write in process during an operating system crash might be only partially written to disk. During recovery, the row changes stored in WAL are not enough to recover. This option writes pages when first modified after a checkpoint to WAL so full recovery is possible.
|
| synchronous_commit
| on | Write-Ahead Log / Settings
| user
| Sets immediate fsync at commit.
|
| wal_buffers
| 8 8kB | Write-Ahead Log / Settings
| postmaster
| Sets the number of disk-page buffers in shared memory for WAL.
|
| wal_sync_method
| open_datasync | Write-Ahead Log / Settings
| sighup
| Selects the method used for forcing WAL updates to disk.
|
| wal_writer_delay
| 200 ms | Write-Ahead Log / Settings
| sighup
| WAL writer sleep time between WAL flushes.
|