archive_command sighup Write-Ahead Log / Archiving STRING Sets the shell command that will be called to archive a WAL file. archive_mode postmaster Write-Ahead Log / Archiving ENUM off Allows archiving of WAL files using archive_command. archive_timeout sighup Write-Ahead Log / Archiving INTEGER 0 0 1073741823 Forces a switch to the next xlog file if a new file has not been started within N seconds. array_nulls user Version and Platform Compatibility / Previous PostgreSQL Versions BOOLEAN FALSE Enable input of NULL elements in arrays. When turned on, unquoted NULL in an array input value means a null value; otherwise it is taken literally. authentication_timeout sighup Connections and Authentication / Security and Authentication INTEGER 0 1 600 Sets the maximum allowed time to complete client authentication. autovacuum sighup Autovacuum BOOLEAN FALSE Starts the autovacuum subprocess. autovacuum_analyze_scale_factor sighup Autovacuum REAL 0 0 100 Number of tuple inserts, updates, or deletes prior to analyze as a fraction of reltuples. autovacuum_analyze_threshold sighup Autovacuum INTEGER 0 0 2147483647 Minimum number of tuple inserts, updates, or deletes prior to analyze. autovacuum_freeze_max_age postmaster Autovacuum INTEGER 0 100000 2000000000 Age at which to autovacuum a table to prevent transaction ID wraparound. autovacuum_max_workers postmaster Autovacuum INTEGER 0 1 262143 Sets the maximum number of simultaneously running autovacuum worker processes. autovacuum_multixact_freeze_max_age postmaster Autovacuum INTEGER 0 10000 2000000000 Multixact age at which to autovacuum a table to prevent multixact wraparound. autovacuum_naptime sighup Autovacuum INTEGER 0 1 2147483 Time to sleep between autovacuum runs. autovacuum_vacuum_cost_delay sighup Autovacuum INTEGER 0 -1 100 Vacuum cost delay in milliseconds, for autovacuum. autovacuum_vacuum_cost_limit sighup Autovacuum INTEGER 0 -1 10000 Vacuum cost amount available before napping, for autovacuum. autovacuum_vacuum_scale_factor sighup Autovacuum REAL 0 0 100 Number of tuple updates or deletes prior to vacuum as a fraction of reltuples. autovacuum_vacuum_threshold sighup Autovacuum INTEGER 0 0 2147483647 Minimum number of tuple updates or deletes prior to vacuum. autovacuum_work_mem sighup Resource Usage / Memory INTEGER 0 -1 2147483647 Sets the maximum memory to be used by each autovacuum worker process. backend_flush_after user Resource Usage / Asynchronous Behavior INTEGER 0 0 256 Number of pages after which previously performed writes are flushed to disk. backslash_quote user Version and Platform Compatibility / Previous PostgreSQL Versions ENUM safe_encoding Sets whether "\'" is allowed in string literals. bgwriter_delay sighup Resource Usage / Background Writer INTEGER 0 10 10000 Background writer sleep time between rounds. bgwriter_flush_after sighup Resource Usage / Background Writer INTEGER 0 0 256 Number of pages after which previously performed writes are flushed to disk. bgwriter_lru_maxpages sighup Resource Usage / Background Writer INTEGER 0 0 1000 Background writer maximum number of LRU pages to flush per round. bgwriter_lru_multiplier sighup Resource Usage / Background Writer REAL 0 0 10 Multiple of the average buffer usage to free per round. bonjour postmaster Connections and Authentication / Connection Settings BOOLEAN FALSE Enables advertising the server via Bonjour. bonjour_name postmaster Connections and Authentication / Connection Settings STRING Sets the Bonjour service name. bytea_output user Client Connection Defaults / Statement Behavior ENUM hex Sets the output format for bytea. check_function_bodies user Client Connection Defaults / Statement Behavior BOOLEAN FALSE Check function bodies during CREATE FUNCTION. checkpoint_completion_target sighup Write-Ahead Log / Checkpoints REAL 0 0 1 Time spent flushing dirty buffers during checkpoint, as fraction of checkpoint interval. checkpoint_flush_after sighup Write-Ahead Log / Checkpoints INTEGER 0 0 256 Number of pages after which previously performed writes are flushed to disk. checkpoint_timeout sighup Write-Ahead Log / Checkpoints INTEGER 0 30 86400 Sets the maximum time between automatic WAL checkpoints. checkpoint_warning sighup Write-Ahead Log / Checkpoints INTEGER 0 0 2147483647 Enables warnings if checkpoint segments are filled more frequently than this. 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. client_encoding user Client Connection Defaults / Locale and Formatting STRING SQL_ASCII Sets the client's character set encoding. client_min_messages user Reporting and Logging / When to Log ENUM notice Sets the message levels that are sent to the client. Each level includes all the levels that follow it. The later the level, the fewer messages are sent. cluster_name postmaster Process Title STRING Sets the name of the cluster, which is included in the process title. commit_delay superuser Write-Ahead Log / Settings INTEGER 0 0 100000 Sets the delay in microseconds between transaction commit and flushing WAL to disk. commit_siblings user Write-Ahead Log / Settings INTEGER 0 0 1000 Sets the minimum concurrent open transactions before performing commit_delay. constraint_exclusion user Query Tuning / Other Planner Options ENUM partition Enables the planner to use constraints to optimize queries. Table scans will be skipped if their constraints guarantee that no rows match the query. cpu_index_tuple_cost user Query Tuning / Planner Cost Constants REAL 0 0 1.79769e+308 Sets the planner's estimate of the cost of processing each index entry during an index scan. cpu_operator_cost user Query Tuning / Planner Cost Constants REAL 0 0 1.79769e+308 Sets the planner's estimate of the cost of processing each operator or function call. cpu_tuple_cost user Query Tuning / Planner Cost Constants REAL 0 0 1.79769e+308 Sets the planner's estimate of the cost of processing each tuple (row). cursor_tuple_fraction user Query Tuning / Other Planner Options REAL 0 0 1 Sets the planner's estimate of the fraction of a cursor's rows that will be retrieved. data_directory postmaster File Locations STRING Sets the server's data directory. DateStyle user Client Connection Defaults / Locale and Formatting STRING ISO, MDY Sets the display format for date and time values. Also controls interpretation of ambiguous date inputs. db_user_namespace sighup Connections and Authentication / Security and Authentication BOOLEAN FALSE Enables per-database user names. deadlock_timeout superuser Lock Management INTEGER 0 1 2147483647 Sets the time to wait on a lock before checking for deadlock. debug_pretty_print user Reporting and Logging / What to Log BOOLEAN FALSE Indents parse and plan tree displays. debug_print_parse user Reporting and Logging / What to Log BOOLEAN FALSE Logs each query's parse tree. debug_print_plan user Reporting and Logging / What to Log BOOLEAN FALSE Logs each query's execution plan. debug_print_rewritten user Reporting and Logging / What to Log BOOLEAN FALSE Logs each query's rewritten parse tree. default_statistics_target user Query Tuning / Other Planner Options INTEGER 0 1 10000 Sets the default statistics target. This applies to table columns that have not had a column-specific target set via ALTER TABLE SET STATISTICS. default_tablespace user Client Connection Defaults / Statement Behavior STRING Sets the default tablespace to create tables and indexes in. An empty string selects the database's default tablespace. default_text_search_config user Client Connection Defaults / Locale and Formatting STRING pg_catalog.simple Sets default text search configuration. default_transaction_deferrable user Client Connection Defaults / Statement Behavior BOOLEAN FALSE Sets the default deferrable status of new transactions. default_transaction_isolation user Client Connection Defaults / Statement Behavior ENUM read committed Sets the transaction isolation level of each new transaction. default_transaction_read_only user Client Connection Defaults / Statement Behavior BOOLEAN FALSE Sets the default read-only status of new transactions. default_with_oids user Version and Platform Compatibility / Previous PostgreSQL Versions BOOLEAN FALSE Create new tables with OIDs by default. dynamic_library_path superuser Client Connection Defaults / Other Defaults STRING $libdir Sets the path for dynamically loadable modules. 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. dynamic_shared_memory_type postmaster Resource Usage / Memory ENUM posix Selects the dynamic shared memory implementation used. effective_cache_size user Query Tuning / Planner Cost Constants INTEGER 0 1 2147483647 Sets the planner's assumption about the size of the disk cache. 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. effective_io_concurrency user Resource Usage / Asynchronous Behavior INTEGER 0 0 1000 Number of simultaneous requests that can be handled efficiently by the disk subsystem. For RAID arrays, this should be approximately the number of drive spindles in the array. enable_bitmapscan user Query Tuning / Planner Method Configuration BOOLEAN FALSE Enables the planner's use of bitmap-scan plans. enable_hashagg user Query Tuning / Planner Method Configuration BOOLEAN FALSE Enables the planner's use of hashed aggregation plans. enable_hashjoin user Query Tuning / Planner Method Configuration BOOLEAN FALSE Enables the planner's use of hash join plans. enable_indexonlyscan user Query Tuning / Planner Method Configuration BOOLEAN FALSE Enables the planner's use of index-only-scan plans. enable_indexscan user Query Tuning / Planner Method Configuration BOOLEAN FALSE Enables the planner's use of index-scan plans. enable_material user Query Tuning / Planner Method Configuration BOOLEAN FALSE Enables the planner's use of materialization. enable_mergejoin user Query Tuning / Planner Method Configuration BOOLEAN FALSE Enables the planner's use of merge join plans. enable_nestloop user Query Tuning / Planner Method Configuration BOOLEAN FALSE Enables the planner's use of nested-loop join plans. enable_seqscan user Query Tuning / Planner Method Configuration BOOLEAN FALSE Enables the planner's use of sequential-scan plans. enable_sort user Query Tuning / Planner Method Configuration BOOLEAN FALSE Enables the planner's use of explicit sort steps. enable_tidscan user Query Tuning / Planner Method Configuration BOOLEAN FALSE Enables the planner's use of TID scan plans. escape_string_warning user Version and Platform Compatibility / Previous PostgreSQL Versions BOOLEAN FALSE Warn about backslash escapes in ordinary string literals. event_source postmaster Reporting and Logging / Where to Log STRING PostgreSQL Sets the application name used to identify PostgreSQL messages in the event log. exit_on_error user Error Handling BOOLEAN FALSE Terminate session on any error. external_pid_file postmaster File Locations STRING Writes the postmaster PID to the specified file. extra_float_digits user Client Connection Defaults / Locale and Formatting INTEGER 0 -15 3 Sets the number of digits displayed for floating-point values. 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). force_parallel_mode user Query Tuning / Other Planner Options ENUM off Forces use of parallel query facilities. If possible, run query using a parallel worker and with parallel restrictions. from_collapse_limit user Query Tuning / Other Planner Options INTEGER 0 1 2147483647 Sets the FROM-list size beyond which subqueries are not collapsed. The planner will merge subqueries into upper queries if the resulting FROM list would have no more than this many items. fsync sighup Write-Ahead Log / Settings BOOLEAN FALSE Forces synchronization of updates to disk. 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 sighup Write-Ahead Log / Settings BOOLEAN FALSE Writes full pages to WAL when first modified after a checkpoint. 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. geqo user Query Tuning / Genetic Query Optimizer BOOLEAN FALSE Enables genetic query optimization. This algorithm attempts to do planning without exhaustive searching. geqo_effort user Query Tuning / Genetic Query Optimizer INTEGER 0 1 10 GEQO: effort is used to set the default for other GEQO parameters. geqo_generations user Query Tuning / Genetic Query Optimizer INTEGER 0 0 2147483647 GEQO: number of iterations of the algorithm. Zero selects a suitable default value. geqo_pool_size user Query Tuning / Genetic Query Optimizer INTEGER 0 0 2147483647 GEQO: number of individuals in the population. Zero selects a suitable default value. geqo_seed user Query Tuning / Genetic Query Optimizer REAL 0 0 1 GEQO: seed for random path selection. geqo_selection_bias user Query Tuning / Genetic Query Optimizer REAL 0 1.5 2 GEQO: selective pressure within the population. geqo_threshold user Query Tuning / Genetic Query Optimizer INTEGER 0 2 2147483647 Sets the threshold of FROM items beyond which GEQO is used. gin_fuzzy_search_limit user Client Connection Defaults / Other Defaults INTEGER 0 0 2147483647 Sets the maximum allowed result for exact search by GIN. gin_pending_list_limit user Client Connection Defaults / Statement Behavior INTEGER 0 64 2147483647 Sets the maximum size of the pending list for GIN index. hba_file postmaster File Locations STRING Sets the server's "hba" configuration file. hot_standby postmaster Replication / Standby Servers BOOLEAN FALSE Allows connections and queries during recovery. hot_standby_feedback sighup Replication / Standby Servers BOOLEAN FALSE Allows feedback from a hot standby to the primary that will avoid query conflicts. huge_pages postmaster Resource Usage / Memory ENUM try Use of huge pages on Linux. ident_file postmaster File Locations STRING Sets the server's "ident" configuration file. idle_in_transaction_session_timeout user Client Connection Defaults / Statement Behavior INTEGER 0 0 2147483647 Sets the maximum allowed duration of any idling transaction. A value of 0 turns off the timeout. IntervalStyle user Client Connection Defaults / Locale and Formatting ENUM postgres Sets the display format for interval values. join_collapse_limit user Query Tuning / Other Planner Options INTEGER 0 1 2147483647 Sets the FROM-list size beyond which JOIN constructs are not flattened. The planner will flatten explicit JOIN constructs into lists of FROM items whenever a list of no more than this many items would result. krb_caseins_users sighup Connections and Authentication / Security and Authentication BOOLEAN FALSE Sets whether Kerberos and GSSAPI user names should be treated as case-insensitive. krb_server_keyfile sighup Connections and Authentication / Security and Authentication STRING FILE:/jet/etc/postgresql/krb5.keytab Sets the location of the Kerberos server key file. lc_messages superuser Client Connection Defaults / Locale and Formatting STRING Sets the language in which messages are displayed. lc_monetary user Client Connection Defaults / Locale and Formatting STRING C Sets the locale for formatting monetary amounts. lc_numeric user Client Connection Defaults / Locale and Formatting STRING C Sets the locale for formatting numbers. lc_time user Client Connection Defaults / Locale and Formatting STRING C Sets the locale for formatting date and time values. listen_addresses postmaster Connections and Authentication / Connection Settings STRING localhost Sets the host name or IP address(es) to listen to. lo_compat_privileges superuser Version and Platform Compatibility / Previous PostgreSQL Versions BOOLEAN FALSE Enables backward compatibility mode for privilege checks on large objects. Skips privilege checks when reading or modifying large objects, for compatibility with PostgreSQL releases prior to 9.0. local_preload_libraries user Client Connection Defaults / Shared Library Preloading STRING Lists unprivileged shared libraries to preload into each backend. lock_timeout user Client Connection Defaults / Statement Behavior INTEGER 0 0 2147483647 Sets the maximum allowed duration of any wait for a lock. A value of 0 turns off the timeout. log_autovacuum_min_duration sighup Reporting and Logging / What to Log INTEGER 0 -1 2147483647 Sets the minimum execution time above which autovacuum actions will be logged. Zero prints all actions. -1 turns autovacuum logging off. log_checkpoints sighup Reporting and Logging / What to Log BOOLEAN FALSE Logs each checkpoint. log_connections superuser-backend Reporting and Logging / What to Log BOOLEAN FALSE Logs each successful connection. log_destination sighup Reporting and Logging / Where to Log STRING stderr Sets the destination for server log output. Valid values are combinations of "stderr", "syslog", "csvlog", and "eventlog", depending on the platform. log_directory sighup Reporting and Logging / Where to Log STRING pg_log Sets the destination directory for log files. Can be specified as relative to the data directory or as absolute path. log_disconnections superuser-backend Reporting and Logging / What to Log BOOLEAN FALSE Logs end of a session, including duration. log_duration superuser Reporting and Logging / What to Log BOOLEAN FALSE Logs the duration of each completed SQL statement. log_error_verbosity superuser Reporting and Logging / What to Log ENUM default Sets the verbosity of logged messages. log_executor_stats superuser Statistics / Monitoring BOOLEAN FALSE Writes executor performance statistics to the server log. log_file_mode sighup Reporting and Logging / Where to Log INTEGER 0 0 511 Sets the file permissions for log files. The parameter value is expected to be a 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).) log_filename sighup Reporting and Logging / Where to Log STRING postgresql-%Y-%m-%d_%H%M%S.log Sets the file name pattern for log files. log_hostname sighup Reporting and Logging / What to Log BOOLEAN FALSE Logs the host name in the connection logs. 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 sighup Reporting and Logging / What to Log STRING Controls information prefixed to each log line. If blank, no prefix is used. log_lock_waits superuser Reporting and Logging / What to Log BOOLEAN FALSE Logs long lock waits. log_min_duration_statement superuser Reporting and Logging / When to Log INTEGER 0 -1 2147483647 Sets the minimum execution time above which statements will be logged. Zero prints all queries. -1 turns this feature off. log_min_error_statement superuser Reporting and Logging / When to Log ENUM error Causes all statements generating error at or above this level to be logged. Each level includes all the levels that follow it. The later the level, the fewer messages are sent. log_min_messages superuser Reporting and Logging / When to Log ENUM warning Sets the message levels that are logged. Each level includes all the levels that follow it. The later the level, the fewer messages are sent. log_parser_stats superuser Statistics / Monitoring BOOLEAN FALSE Writes parser performance statistics to the server log. log_planner_stats superuser Statistics / Monitoring BOOLEAN FALSE Writes planner performance statistics to the server log. log_replication_commands superuser Reporting and Logging / What to Log BOOLEAN FALSE Logs each replication command. log_rotation_age sighup Reporting and Logging / Where to Log INTEGER 0 0 35791394 Automatic log file rotation will occur after N minutes. log_rotation_size sighup Reporting and Logging / Where to Log INTEGER 0 0 2097151 Automatic log file rotation will occur after N kilobytes. log_statement superuser Reporting and Logging / What to Log ENUM none Sets the type of statements logged. log_statement_stats superuser Statistics / Monitoring BOOLEAN FALSE Writes cumulative performance statistics to the server log. log_temp_files superuser Reporting and Logging / What to Log INTEGER 0 -1 2147483647 Log the use of temporary files larger than this number of kilobytes. Zero logs all files. The default is -1 (turning this feature off). log_timezone sighup Reporting and Logging / What to Log STRING GMT Sets the time zone to use in log messages. log_truncate_on_rotation sighup Reporting and Logging / Where to Log BOOLEAN FALSE Truncate existing log files of same name during log rotation. logging_collector postmaster Reporting and Logging / Where to Log BOOLEAN FALSE Start a subprocess to capture stderr output and/or csvlogs into log files. maintenance_work_mem user Resource Usage / Memory INTEGER 0 1024 2147483647 Sets the maximum memory to be used for maintenance operations. This includes operations such as VACUUM and CREATE INDEX. max_connections postmaster Connections and Authentication / Connection Settings INTEGER 0 1 262143 Sets the maximum number of concurrent connections. max_files_per_process postmaster Resource Usage / Kernel Resources INTEGER 0 25 2147483647 Sets the maximum number of simultaneously open files for each server process. max_locks_per_transaction postmaster Lock Management INTEGER 0 10 2147483647 Sets the maximum number of locks per transaction. 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. max_parallel_workers_per_gather user Resource Usage / Asynchronous Behavior INTEGER 0 0 1024 Sets the maximum number of parallel processes per executor node. max_pred_locks_per_transaction postmaster Lock Management INTEGER 0 10 2147483647 Sets the maximum number of predicate locks per transaction. The shared predicate lock table is sized on the assumption that at most max_pred_locks_per_transaction * max_connections distinct objects will need to be locked at any one time. max_prepared_transactions postmaster Resource Usage / Memory INTEGER 0 0 262143 Sets the maximum number of simultaneously prepared transactions. max_replication_slots postmaster Replication / Sending Servers INTEGER 0 0 262143 Sets the maximum number of simultaneously defined replication slots. max_stack_depth superuser Resource Usage / Memory INTEGER 0 100 2147483647 Sets the maximum stack depth, in kilobytes. max_standby_archive_delay sighup Replication / Standby Servers INTEGER 0 -1 2147483647 Sets the maximum delay before canceling queries when a hot standby server is processing archived WAL data. max_standby_streaming_delay sighup Replication / Standby Servers INTEGER 0 -1 2147483647 Sets the maximum delay before canceling queries when a hot standby server is processing streamed WAL data. max_wal_senders postmaster Replication / Sending Servers INTEGER 0 0 262143 Sets the maximum number of simultaneously running WAL sender processes. max_wal_size sighup Write-Ahead Log / Checkpoints INTEGER 0 2 2147483647 Sets the WAL size that triggers a checkpoint. max_worker_processes postmaster Resource Usage / Asynchronous Behavior INTEGER 0 0 262143 Maximum number of concurrent worker processes. min_parallel_relation_size user Query Tuning / Planner Cost Constants INTEGER 0 0 715827882 Sets the minimum size of relations to be considered for parallel scan. min_wal_size sighup Write-Ahead Log / Checkpoints INTEGER 0 2 2147483647 Sets the minimum size to shrink the WAL to. old_snapshot_threshold postmaster Resource Usage / Asynchronous Behavior INTEGER 0 -1 86400 Time before a snapshot is too old to read pages changed after the snapshot was taken. A value of -1 disables this feature. operator_precedence_warning user Version and Platform Compatibility / Previous PostgreSQL Versions BOOLEAN FALSE Emit a warning for constructs that changed meaning since PostgreSQL 9.4. parallel_setup_cost user Query Tuning / Planner Cost Constants REAL 0 0 1.79769e+308 Sets the planner's estimate of the cost of starting up worker processes for parallel query. parallel_tuple_cost user Query Tuning / Planner Cost Constants REAL 0 0 1.79769e+308 Sets the planner's estimate of the cost of passing each tuple (row) from worker to master backend. password_encryption user Connections and Authentication / Security and Authentication BOOLEAN FALSE Encrypt passwords. 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. port postmaster Connections and Authentication / Connection Settings INTEGER 0 1 65535 Sets the TCP port the server listens on. ptrack_enable sighup Write-Ahead Log / Settings BOOLEAN FALSE Enable page tracking. quote_all_identifiers user Version and Platform Compatibility / Previous PostgreSQL Versions BOOLEAN FALSE When generating SQL fragments, quote all identifiers. random_page_cost user Query Tuning / Planner Cost Constants REAL 0 0 1.79769e+308 Sets the planner's estimate of the cost of a nonsequentially fetched disk page. replacement_sort_tuples user Resource Usage / Memory INTEGER 0 0 2147483647 Sets the maximum number of tuples to be sorted using replacement selection. When more tuples than this are present, quicksort will be used. restart_after_crash sighup Error Handling BOOLEAN FALSE Reinitialize server after backend crash. row_security user Connections and Authentication / Security and Authentication BOOLEAN FALSE Enable row security. When enabled, row security will be applied to all users. search_path user Client Connection Defaults / Statement Behavior STRING "$user", public Sets the schema search order for names that are not schema-qualified. seq_page_cost user Query Tuning / Planner Cost Constants REAL 0 0 1.79769e+308 Sets the planner's estimate of the cost of a sequentially fetched disk page. session_preload_libraries superuser Client Connection Defaults / Shared Library Preloading STRING Lists shared libraries to preload into each backend. session_replication_role superuser Client Connection Defaults / Statement Behavior ENUM origin Sets the session's behavior for triggers and rewrite rules. shared_buffers postmaster Resource Usage / Memory INTEGER 0 16 1073741823 Sets the number of shared memory buffers used by the server. shared_preload_libraries postmaster Client Connection Defaults / Shared Library Preloading STRING Lists shared libraries to preload into server. sql_inheritance user Version and Platform Compatibility / Previous PostgreSQL Versions BOOLEAN FALSE Causes subtables to be included by default in various commands. ssl postmaster Connections and Authentication / Security and Authentication BOOLEAN FALSE Enables SSL connections. ssl_ca_file postmaster Connections and Authentication / Security and Authentication STRING Location of the SSL certificate authority file. ssl_cert_file postmaster Connections and Authentication / Security and Authentication STRING server.crt Location of the SSL server certificate file. ssl_ciphers postmaster Connections and Authentication / Security and Authentication STRING HIGH:MEDIUM:+3DES:!aNULL Sets the list of allowed SSL ciphers. ssl_crl_file postmaster Connections and Authentication / Security and Authentication STRING Location of the SSL certificate revocation list file. ssl_ecdh_curve postmaster Connections and Authentication / Security and Authentication STRING prime256v1 Sets the curve to use for ECDH. ssl_key_file postmaster Connections and Authentication / Security and Authentication STRING server.key Location of the SSL server private key file. ssl_prefer_server_ciphers postmaster Connections and Authentication / Security and Authentication BOOLEAN FALSE Give priority to server ciphersuite order. standard_conforming_strings user Version and Platform Compatibility / Previous PostgreSQL Versions BOOLEAN FALSE Causes '...' strings to treat backslashes literally. statement_timeout user Client Connection Defaults / Statement Behavior INTEGER 0 0 2147483647 Sets the maximum allowed duration of any statement. A value of 0 turns off the timeout. stats_temp_directory sighup Statistics / Query and Index Statistics Collector STRING pg_stat_tmp Writes temporary statistics files to the specified directory. superuser_reserved_connections postmaster Connections and Authentication / Connection Settings INTEGER 0 0 262143 Sets the number of connection slots reserved for superusers. synchronize_seqscans user Version and Platform Compatibility / Previous PostgreSQL Versions BOOLEAN FALSE Enable synchronized sequential scans. synchronous_commit user Write-Ahead Log / Settings ENUM on Sets the current transaction's synchronization level. synchronous_standby_names sighup Replication / Master Server STRING Number of synchronous standbys and list of names of potential synchronous ones. syslog_facility sighup Reporting and Logging / Where to Log ENUM local0 Sets the syslog "facility" to be used when syslog enabled. syslog_ident sighup Reporting and Logging / Where to Log STRING postgres Sets the program name used to identify PostgreSQL messages in syslog. syslog_sequence_numbers sighup Reporting and Logging / Where to Log BOOLEAN FALSE Add sequence number to syslog messages to avoid duplicate suppression. syslog_split_messages sighup Reporting and Logging / Where to Log BOOLEAN FALSE Split messages sent to syslog by lines and to fit into 1024 bytes. tcp_keepalives_count user Client Connection Defaults / Other Defaults INTEGER 0 0 2147483647 Maximum number of TCP keepalive retransmits. 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 user Client Connection Defaults / Other Defaults INTEGER 0 0 2147483647 Time between issuing TCP keepalives. A value of 0 uses the system default. tcp_keepalives_interval user Client Connection Defaults / Other Defaults INTEGER 0 0 2147483647 Time between TCP keepalive retransmits. A value of 0 uses the system default. temp_buffers user Resource Usage / Memory INTEGER 0 100 1073741823 Sets the maximum number of temporary buffers used by each session. temp_file_limit superuser Resource Usage / Disk INTEGER 0 -1 2147483647 Limits the total size of all temporary files used by each process. -1 means no limit. temp_tablespaces user Client Connection Defaults / Statement Behavior STRING Sets the tablespace(s) to use for temporary tables and sort files. TimeZone user Client Connection Defaults / Locale and Formatting STRING GMT Sets the time zone for displaying and interpreting time stamps. timezone_abbreviations user Client Connection Defaults / Locale and Formatting STRING Selects a file of time zone abbreviations. trace_recovery_messages sighup Developer Options ENUM log Enables logging of recovery-related debugging information. Each level includes all the levels that follow it. The later the level, the fewer messages are sent. track_activities superuser Statistics / Query and Index Statistics Collector BOOLEAN FALSE Collects information about executing commands. Enables the collection of information on the currently executing command of each session, along with the time at which that command began execution. track_activity_query_size postmaster Resource Usage / Memory INTEGER 0 100 102400 Sets the size reserved for pg_stat_activity.query, in bytes. track_commit_timestamp postmaster Replication BOOLEAN FALSE Collects transaction commit time. track_counts superuser Statistics / Query and Index Statistics Collector BOOLEAN FALSE Collects statistics on database activity. track_functions superuser Statistics / Query and Index Statistics Collector ENUM none Collects function-level statistics on database activity. track_io_timing superuser Statistics / Query and Index Statistics Collector BOOLEAN FALSE Collects timing statistics for database I/O activity. transform_null_equals user Version and Platform Compatibility / Other Platforms and Clients BOOLEAN FALSE Treats "expr=NULL" as "expr IS NULL". 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). unix_socket_directories postmaster Connections and Authentication / Connection Settings STRING /jet/run/postgresql, /jet/run/postgresql Sets the directories where Unix-domain sockets will be created. unix_socket_group postmaster Connections and Authentication / Connection Settings STRING Sets the owning group of the Unix-domain socket. The owning user of the socket is always the user that starts the server. unix_socket_permissions postmaster Connections and Authentication / Connection Settings INTEGER 0 0 511 Sets the access permissions of the Unix-domain socket. Unix-domain sockets use the usual Unix file system permission set. The parameter value is expected to be a 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).) update_process_title superuser Process Title BOOLEAN FALSE Updates the process title to show the active SQL command. Enables updating of the process title every time a new SQL command is received by the server. vacuum_cost_delay user Resource Usage / Cost-Based Vacuum Delay INTEGER 0 0 100 Vacuum cost delay in milliseconds. vacuum_cost_limit user Resource Usage / Cost-Based Vacuum Delay INTEGER 0 1 10000 Vacuum cost amount available before napping. vacuum_cost_page_dirty user Resource Usage / Cost-Based Vacuum Delay INTEGER 0 0 10000 Vacuum cost for a page dirtied by vacuum. vacuum_cost_page_hit user Resource Usage / Cost-Based Vacuum Delay INTEGER 0 0 10000 Vacuum cost for a page found in the buffer cache. vacuum_cost_page_miss user Resource Usage / Cost-Based Vacuum Delay INTEGER 0 0 10000 Vacuum cost for a page not found in the buffer cache. vacuum_defer_cleanup_age sighup Replication / Master Server INTEGER 0 0 1000000 Number of transactions by which VACUUM and HOT cleanup should be deferred, if any. vacuum_freeze_min_age user Client Connection Defaults / Statement Behavior INTEGER 0 0 1000000000 Minimum age at which VACUUM should freeze a table row. vacuum_freeze_table_age user Client Connection Defaults / Statement Behavior INTEGER 0 0 2000000000 Age at which VACUUM should scan whole table to freeze tuples. vacuum_multixact_freeze_min_age user Client Connection Defaults / Statement Behavior INTEGER 0 0 1000000000 Minimum age at which VACUUM should freeze a MultiXactId in a table row. vacuum_multixact_freeze_table_age user Client Connection Defaults / Statement Behavior INTEGER 0 0 2000000000 Multixact age at which VACUUM should scan whole table to freeze tuples. wal_buffers postmaster Write-Ahead Log / Settings INTEGER 0 -1 262143 Sets the number of disk-page buffers in shared memory for WAL. wal_compression superuser Write-Ahead Log / Settings BOOLEAN FALSE Compresses full-page writes written in WAL file. wal_keep_segments sighup Replication / Sending Servers INTEGER 0 0 2147483647 Sets the number of WAL files held for standby servers. wal_level postmaster Write-Ahead Log / Settings ENUM minimal Set the level of information written to the WAL. wal_log_hints postmaster Write-Ahead Log / Settings BOOLEAN FALSE Writes full pages to WAL when first modified after a checkpoint, even for a non-critical modifications. wal_receiver_status_interval sighup Replication / Standby Servers INTEGER 0 0 2147483 Sets the maximum interval between WAL receiver status reports to the primary. wal_receiver_timeout sighup Replication / Standby Servers INTEGER 0 0 2147483647 Sets the maximum wait time to receive data from the primary. wal_retrieve_retry_interval sighup Replication / Standby Servers INTEGER 0 1 2147483647 Sets the time to wait before retrying to retrieve WAL after a failed attempt. wal_sender_timeout sighup Replication / Sending Servers INTEGER 0 0 2147483647 Sets the maximum time to wait for WAL replication. wal_sync_method sighup Write-Ahead Log / Settings ENUM fdatasync Selects the method used for forcing WAL updates to disk. wal_writer_delay sighup Write-Ahead Log / Settings INTEGER 0 1 10000 Time between WAL flushes performed in the WAL writer. wal_writer_flush_after sighup Write-Ahead Log / Settings INTEGER 0 0 2147483647 Amount of WAL written out by WAL writer that triggers a flush. work_mem user Resource Usage / Memory INTEGER 0 64 2147483647 Sets the maximum memory to be used for query workspaces. This much memory can be used by each internal sort operation and hash table before switching to temporary disk files. xmlbinary user Client Connection Defaults / Statement Behavior ENUM base64 Sets how binary values are to be encoded in XML. xmloption user Client Connection Defaults / Statement Behavior ENUM content Sets whether XML data in implicit parsing and serialization operations is to be considered as documents or content fragments.