Parameters for Azure HorizonDB (Preview)

Azure HorizonDB provides a set of configurable parameters for each cluster.

These parameters can correspond to:

• Database engine: parameters defined by the PostgreSQL database engine or by binary libraries that implement functionality of extensions. Some examples of database engine built-in parameters are autovacuum_max_workers, DateStyle, client_min_messages, password_encryption, max_connections, geqo, from_collapse_limit, cpu_tuple_cost, cpu_tuple_cost, max_standby_streaming_delay, log_connections, log_min_duration_statement, max_parallel_workers, bgwriter_delay, and shared_buffers. Some examples of parameters defined by extensions are pg_qs.max_query_text_length (pg_qs extension, implementing functionality for query store), pg_stat_statements.max (pg_stat_statements extension), pgaudit.log_catalog (pgaudit extension), and cron.database_name (cron extension).
• Non-database engine: parameters that control some built-in functionality, which is core to the Azure HorizonDB service, but isn't part of the database engine or any of its extensions.

Customize parameters

Both, database engine and non-database engine parameters can be configured at the cluster level. In Azure HorizonDB, parameters at the cluster level are managed through parameter groups.

Note

Because Azure HorizonDB is a managed database service, users don't have host or operating system access to view or modify configuration files such as postgresql.conf. The content of the files is automatically updated based on parameter changes that you make.

Database engine parameters can also be configured at more granular scopes. These adjustments override globally set values. Their scope and duration depend on the level at which you make them:

• Database level: Use the ALTER DATABASE command for database-specific configurations.

• Role or user level: Use the ALTER USER command for user-centric settings.

• Function, procedure level: When you're defining a function or procedure, you can specify or alter the configuration parameters that are used when the function is called.

• Table level: As an example, you can modify parameters related to autovacuum at this level.

• Session level: For the life of an individual database session, you can adjust specific parameters. PostgreSQL facilitates this adjustment with the following SQL commands:

  • Use the SET command to make session-specific adjustments. These changes serve as the default settings during the current session. Access to these changes might require specific SET privileges, and the limitations for modifiable and read-only parameters described earlier don't apply. The corresponding SQL function is set_config(setting_name, new_value, is_local).
  • Use the SHOW command to examine existing parameter settings. Its SQL function equivalent is current_setting(setting_name text).

Work with time zone parameters

If you plan to work with date and time data in PostgreSQL, make sure that you set the correct time zone for your location. All timezone-aware dates and times are stored internally in PostgreSQL in UTC. They're converted to local time in the zone specified by the TimeZone cluster parameter before being displayed to the client. This parameter can be edited in a non-default parameter group which overrides the value of that parameter, and then that parameter group has to be connected to the clusters on which you want that value to be in effect.

PostgreSQL allows you to specify time zones in three different forms:

• A full time zone name, for example America/New_York. The recognized time zone names are listed in the pg_timezone_names view. Example to query this view in psql and get list of time zone names:

  select name FROM pg_timezone_names LIMIT 20;

  You should see result set like:

           name
       -----------------------
       GMT0
       Iceland
       Factory
       NZ-CHAT
       America/Panama
       America/Fort_Nelson
       America/Pangnirtung
       America/Belem
       America/Coral_Harbour
       America/Guayaquil
       America/Marigot
       America/Barbados
       America/Porto_Velho
       America/Bogota
       America/Menominee
       America/Martinique
       America/Asuncion
       America/Toronto
       America/Tortola
       America/Managua
       (20 rows)
  

• A time zone abbreviation, for example PST. Such a specification merely defines a particular offset from UTC, in contrast to full time zone names which can imply a set of daylight savings transition-date rules as well. The recognized abbreviations are listed in the pg_timezone_abbrevs view Example to query this view in psql and get list of time zone abbreviations:

   select abbrev from pg_timezone_abbrevs limit 20;

  You should see result set like:

     abbrev|
     ------+
     ACDT |
     ACSST |
     ACST |
     ACT |
     ACWST |
     ADT |
     AEDT |
     AESST |
     AEST |
     AFT |
     AKDT |
     AKST |
     ALMST |
     ALMT |
     AMST |
     AMT |
     ANAST |
     ANAT |
     ARST |
     ART |
  

• In addition to the timezone names and abbreviations PostgreSQL accepts POSIX-style time zone specifications of the form STDoffset or STDoffsetDST. STD is a zone abbreviation. Offset is a numeric offset in hours west from UTC. DST is an optional daylight-savings zone abbreviation, assumed to stand for one hour ahead of the given offset.

Supported parameters

Adaptive Autovacuum

Name	Versions	Description
adaptive_autovacuum.open_transaction_threshold	17	Specifies the timeout, in seconds, before an orphan transaction is rolled back and before a long running transaction is terminated.
adaptive_autovacuum.optimize_configurations	17	Configures parameter tuning as disabled ('OFF') or enabled to tune and update autovacuum parameters.

Autovacuum

Name	Versions	Description
autovacuum	17	Starts the autovacuum subprocess.
autovacuum_analyze_scale_factor	17	Number of tuple inserts, updates, or deletes prior to analyze as a fraction of reltuples.
autovacuum_analyze_threshold	17	Minimum number of tuple inserts, updates, or deletes prior to analyze.
autovacuum_freeze_max_age	17	Age at which to autovacuum a table to prevent transaction ID wraparound.
autovacuum_max_workers	17	Sets the maximum number of simultaneously running autovacuum worker processes.
autovacuum_multixact_freeze_max_age	17	Multixact age at which to autovacuum a table to prevent multixact wraparound.
autovacuum_naptime	17	Time to sleep between autovacuum runs.
autovacuum_vacuum_cost_delay	17	Vacuum cost delay in milliseconds, for autovacuum.
autovacuum_vacuum_cost_limit	17	Vacuum cost amount available before napping, for autovacuum.
autovacuum_vacuum_insert_scale_factor	17	Number of tuple inserts prior to vacuum as a fraction of reltuples.
autovacuum_vacuum_insert_threshold	17	Minimum number of tuple inserts prior to vacuum, or -1 to disable insert vacuums.
autovacuum_vacuum_scale_factor	17	Number of tuple updates or deletes prior to vacuum as a fraction of reltuples.
autovacuum_vacuum_threshold	17	Minimum number of tuple updates or deletes prior to vacuum.

Client Connection Defaults / Locale and Formatting

Name	Versions	Description
client_encoding	17	Sets the client's character set encoding.
DateStyle	17	Sets the display format for date and time values. Also controls interpretation of ambiguous date inputs.
default_text_search_config	17	Sets default text search configuration.
extra_float_digits	17	Sets the number of digits displayed for floating-point values. This affects real, double precision, and geometric data types. A zero or negative parameter value is added to the standard number of digits (FLT_DIG or DBL_DIG as appropriate). Any value greater than zero selects precise output mode.
icu_validation_level	17	Log level for reporting invalid ICU locale strings.
IntervalStyle	17	Sets the display format for interval values.
lc_messages	17	Sets the language in which messages are displayed.
lc_monetary	17	Sets the locale for formatting monetary amounts.
lc_numeric	17	Sets the locale for formatting numbers.
lc_time	17	Sets the locale for formatting date and time values.
TimeZone	17	Sets the time zone for displaying and interpreting time stamps.
timezone_abbreviations	17	Selects a file of time zone abbreviations.

Client Connection Defaults / Other Defaults

Name	Versions	Description
dynamic_library_path	17	Sets the path for dynamically loadable modules. If a dynamically loadable module needs to be opened and the specified name doesn't have a directory component (i.e., the name doesn't contain a slash), the system will search this path for the specified file.
gin_fuzzy_search_limit	17	Sets the maximum allowed result for exact search by GIN.

Client Connection Defaults / Shared Library Preloading

Name	Versions	Description
jit_provider	17	JIT provider to use.
local_preload_libraries	17	Lists unprivileged shared libraries to preload into each backend.
session_preload_libraries	17	Lists shared libraries to preload into each backend.
shared_preload_libraries	17	Lists shared libraries to preload into server.

Client Connection Defaults / Statement Behavior

Name	Versions	Description
bytea_output	17	Sets the output format for bytea.
check_function_bodies	17	Check routine bodies during CREATE FUNCTION and CREATE PROCEDURE.
client_min_messages	17	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.
createrole_self_grant	17	Sets whether a CREATEROLE user automatically grants the role to themselves, and with which options.
default_table_access_method	17	Sets the default table access method for new tables.
default_tablespace	17	Sets the default tablespace to create tables and indexes in. An empty string selects the database's default tablespace.
default_toast_compression	17	Sets the default compression method for compressible values.
default_transaction_deferrable	17	Sets the default deferrable status of new transactions.
default_transaction_isolation	17	Sets the transaction isolation level of each new transaction.
default_transaction_read_only	17	Sets the default read-only status of new transactions.
event_triggers	17	Enables event triggers. When enabled, event triggers will fire for all applicable statements.
gin_pending_list_limit	17	Sets the maximum size of the pending list for GIN index.
idle_in_transaction_session_timeout	17	Sets the maximum allowed idle time between queries, when in a transaction. A value of 0 turns off the timeout.
idle_session_timeout	17	Sets the maximum allowed idle time between queries, when not in a transaction. A value of 0 turns off the timeout.
lock_timeout	17	Sets the maximum allowed duration of any wait for a lock. A value of 0 turns off the timeout.
restrict_nonsystem_relation_kind	17	Prohibits access to non-system relations of specified kinds.
row_security	17	Enable row security. When enabled, row security will be applied to all users.
search_path	17	Sets the schema search order for names that aren't schema-qualified.
session_replication_role	17	Sets the session's behavior for triggers and rewrite rules.
statement_timeout	17	Sets the maximum allowed duration of any statement. A value of 0 turns off the timeout.
temp_tablespaces	17	Sets the tablespace(s) to use for temporary tables and sort files.
transaction_deferrable	17	Whether to defer a read-only serializable transaction until it can be executed with no possible serialization failures.
transaction_isolation	17	Sets the current transaction's isolation level.
transaction_read_only	17	Sets the current transaction's read-only status.
transaction_timeout	17	Sets the maximum allowed duration of any transaction within a session (not a prepared transaction). A value of 0 turns off the timeout.
vacuum_failsafe_age	17	Age at which VACUUM should trigger failsafe to avoid a wraparound outage.
vacuum_freeze_min_age	17	Minimum age at which VACUUM should freeze a table row.
vacuum_freeze_table_age	17	Age at which VACUUM should scan whole table to freeze tuples.
vacuum_multixact_failsafe_age	17	Multixact age at which VACUUM should trigger failsafe to avoid a wraparound outage.
vacuum_multixact_freeze_min_age	17	Minimum age at which VACUUM should freeze a MultiXactId in a table row.
vacuum_multixact_freeze_table_age	17	Multixact age at which VACUUM should scan whole table to freeze tuples.
xmlbinary	17	Sets how binary values are to be encoded in XML.
xmloption	17	Sets whether XML data in implicit parsing and serialization operations is to be considered as documents or content fragments.

Connections and Authentication / Authentication

Name	Versions	Description
authentication_timeout	17	Sets the maximum allowed time to complete client authentication.
db_user_namespace	17	Enables per-database user names.
gss_accept_delegation	17	Sets whether GSSAPI delegation should be accepted from the client.
krb_caseins_users	17	Sets whether Kerberos and GSSAPI user names should be treated as case-insensitive.
krb_server_keyfile	17	Sets the location of the Kerberos server key file.
password_encryption	17	Chooses the algorithm for encrypting passwords.
scram_iterations	17	Sets the iteration count for SCRAM secret generation.

Connections and Authentication / Connection Settings

Name	Versions	Description
bonjour	17	Enables advertising the server via Bonjour.
bonjour_name	17	Sets the Bonjour service name.
listen_addresses	17	Sets the host name or IP address(es) to listen to.
max_connections	17	Sets the maximum number of concurrent connections.
port	17	Sets the TCP port the server listens on.
reserved_connections	17	Sets the number of connection slots reserved for roles with privileges of pg_use_reserved_connections.
superuser_reserved_connections	17	Sets the number of connection slots reserved for superusers.
unix_socket_directories	17	Sets the directories where Unix-domain sockets will be created.
unix_socket_group	17	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	17	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).).

Connections and Authentication / SSL

Name	Versions	Description
ssl	17	Enables SSL connections.
ssl_ca_file	17	Location of the SSL certificate authority file.
ssl_cert_file	17	Location of the SSL server certificate file.
ssl_ciphers	17	Sets the list of allowed SSL ciphers.
ssl_crl_dir	17	Location of the SSL certificate revocation list directory.
ssl_crl_file	17	Location of the SSL certificate revocation list file.
ssl_dh_params_file	17	Location of the SSL DH parameters file.
ssl_ecdh_curve	17	Sets the curve to use for ECDH.
ssl_key_file	17	Location of the SSL server private key file.
ssl_max_protocol_version	17	Sets the maximum SSL/TLS protocol version to use.
ssl_min_protocol_version	17	Sets the minimum SSL/TLS protocol version to use.
ssl_passphrase_command	17	Command to obtain passphrases for SSL.
ssl_passphrase_command_supports_reload	17	Controls whether "ssl_passphrase_command" is called during server reload.
ssl_prefer_server_ciphers	17	Give priority to server ciphersuite order.

Connections and Authentication / TCP Settings

Name	Versions	Description
client_connection_check_interval	17	Sets the time interval between checks for disconnection while running queries.
tcp_keepalives_count	17	Maximum number of TCP keepalive retransmits. 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	17	Time between issuing TCP keepalives. A value of 0 uses the system default.
tcp_keepalives_interval	17	Time between TCP keepalive retransmits. A value of 0 uses the system default.
tcp_user_timeout	17	TCP user timeout. A value of 0 uses the system default.

Customized Options

Name	Versions	Description
anon.algorithm	17	The hash method used for pseudonymizing functions.
anon.k_anonymity_provider	17	The security label provider used for k-anonymity.
anon.masking_policies	17	Define multiple masking policies (NOT IMPLEMENTED YET).
anon.maskschema	17	The schema where the dynamic masking views are stored.
anon.privacy_by_default	17	Mask all columns with NULL (or the default value for NOT NULL columns).
anon.restrict_to_trusted_schemas	17	Masking filters must be in a trusted schema. Activate this option to prevent non-superuser from using their own masking filters.
anon.salt	17	The salt value used for the pseudonymizing functions.
anon.sourceschema	17	The schema where the table are masked by the dynamic masking engine.
anon.strict_mode	17	A masking rule can't change a column data type, unless you disable this. Disabling the mode isn't recommended.
anon.transparent_dynamic_masking	17	New masking engine (EXPERIMENTAL).
auto_explain.log_analyze	17	Use EXPLAIN ANALYZE for plan logging.
auto_explain.log_buffers	17	Log buffers usage.
auto_explain.log_format	17	EXPLAIN format to be used for plan logging.
auto_explain.log_level	17	Log level for the plan.
auto_explain.log_min_duration	17	Sets the minimum execution time above which plans will be logged. Zero prints all plans. -1 turns this feature off.
auto_explain.log_nested_statements	17	Log nested statements.
auto_explain.log_parameter_max_length	17	Sets the maximum length of query parameters to log. Zero logs no query parameters, -1 logs them in full.
auto_explain.log_settings	17	Log modified configuration parameters affecting query planning.
auto_explain.log_timing	17	Collect timing data, not just row counts.
auto_explain.log_triggers	17	Include trigger statistics in plans. This has no effect unless log_analyze is also set.
auto_explain.log_verbose	17	Use EXPLAIN VERBOSE for plan logging.
auto_explain.log_wal	17	Log WAL usage.
auto_explain.sample_rate	17	Fraction of queries to process.
azure.accepted_password_auth_method	17	Password authentication methods, separated by comma, that are accepted by the server.
azure_cdc.change_batch_buffer_size	17	Buffer size, in megabytes, for change batches. These buffers are used to temporarily store CDC changes before they are written to disk.
azure_cdc.change_batch_export_timeout	17	Maximum time, in seconds, to wait before a batch of changes is ready to be exported.
azure_cdc.max_fabric_mirrors	17	Maximum number of parallel fabric mirrors that can be run at the same time.
azure_cdc.max_snapshot_workers	17	Maximum number of workers launched for snapshot export. Each worker exports one table at a time.
azure_cdc.onelake_buffer_size	17	Buffer size, in megabytes, for upload to Onelake. Onelake uploads files in chunks, buffering the data in memory up to this limit.
azure_cdc.parquet_compression	17	Compression algorithm to use for parquet files. Determines the compression algorithm to use for parquet files. Supported values are 'uncompressed', 'snappy', 'gzip', and 'zstd'.
azure_cdc.snapshot_buffer_size	17	Buffer size, in megabytes, for snapshot data files. These buffers are used for writing snapshot data. While this indirectly influences the file size, the actual file size might be smaller due to compression and other factors.
azure_cdc.snapshot_export_timeout	17	Maximum time, in minutes, to wait before reporting an error when exporting a snapshot of a database.
azure.enable_temp_tablespaces_on_local_ssd	17	Stores temporary objects on local Solid State Disk.
azure.extensions	17	List of extensions, separated by comma, that are allowlisted. If an extension isn't in this list, trying to execute CREATE, ALTER, COMMENT, DROP EXTENSION statements on that extension fails.
azure.fabric_mirror_enabled	17	Validates prerequisites for Fabric Mirroring to function properly. Validation only occurs at the very moment this setting is changed from 'off' to 'on'.
azure_storage.blob_block_size_mb	17	Size of blob block, in megabytes, for PUT blob operations.
credcheck.auth_delay_ms	17	Milliseconds to delay before reporting authentication failure.
credcheck.auth_failure_cache_size	17	Maximum of entries in the auth failure cache.
credcheck.encrypted_password_allowed	17	Allow encrypted password to be used or throw an error.
credcheck.history_max_size	17	Maximum of entries in the password history.
credcheck.max_auth_failure	17	Maximum number of authentication failures before the user login account is invalidated.
credcheck.password_contain	17	Password should contain these characters
credcheck.password_contain_username	17	Password contains username
credcheck.password_ignore_case	17	Ignore case while password checking
credcheck.password_min_digit	17	Minimum password digits
credcheck.password_min_length	17	Minimum password length
credcheck.password_min_lower	17	Minimum password lowercase letters
credcheck.password_min_repeat	17	Minimum password characters repeat
credcheck.password_min_special	17	Minimum special characters
credcheck.password_min_upper	17	Minimum password uppercase letters
credcheck.password_not_contain	17	Password shouldn't contain these characters
credcheck.password_reuse_history	17	Minimum number of password changes before permitting reuse
credcheck.password_reuse_interval	17	Minimum number of days elapsed before permitting reuse
credcheck.password_valid_max	17	Force use of VALID UNTIL clause in CREATE ROLE statement with a maximum number of days
credcheck.password_valid_until	17	Force use of VALID UNTIL clause in CREATE ROLE statement with a minimum number of days
credcheck.reset_superuser	17	Restore superuser access when they have been banned.
credcheck.username_contain	17	Username should contain these characters
credcheck.username_contain_password	17	Username contains password
credcheck.username_ignore_case	17	Ignore case while username checking
credcheck.username_min_digit	17	Minimum username digits
credcheck.username_min_length	17	Minimum username length
credcheck.username_min_lower	17	Minimum username lowercase letters
credcheck.username_min_repeat	17	Minimum username characters repeat
credcheck.username_min_special	17	Minimum username special characters
credcheck.username_min_upper	17	Minimum username uppercase letters
credcheck.username_not_contain	17	Username shouldn't contain these characters
credcheck.whitelist	17	Comma separated list of usernames to exclude from password policy check.
credcheck.whitelist_auth_failure	17	Comma separated list of usernames to exclude from max authentication failure check.
cron.database_name	17	Database in which pg_cron metadata is kept.
cron.enable_superuser_jobs	17	Allow jobs to be scheduled as superuser.
cron.host	17	Hostname to connect to postgres. This setting has no effect when background workers are used.
cron.launch_active_jobs	17	Launch jobs that are defined as active.
cron.log_min_messages	17	log_min_messages for the launcher bgworker.
cron.log_run	17	Log all jobs runs into the job_run_details table.
cron.log_statement	17	Log all cron statements prior to execution.
cron.max_running_jobs	17	Maximum number of jobs that can run concurrently.
cron.timezone	17	Specify timezone used for cron schedule.
cron.use_background_workers	17	Use background workers instead of client sessions.
pgaadauth.enable_group_sync	17	Enables synchronization of Microsoft Entra ID group members.
pgaudit.log	17	Specifies which classes of statements will be logged by session audit logging. Multiple classes can be provided using a comma-separated list and classes can be subtracted by prefacing the class with a - sign.
pgaudit.log_catalog	17	Specifies that session logging should be enabled in the case where all relations in a statement are in pg_catalog. Disabling this setting will reduce noise in the log from tools like psql and PgAdmin that query the catalog heavily.
pgaudit.log_client	17	Specifies whether audit messages should be visible to the client. This setting should generally be left disabled but might be useful for debugging or other purposes.
pgaudit.log_level	17	Specifies the log level that will be used for log entries. This setting is used for regression testing and might also be useful to end users for testing or other purposes. It's not intended to be used in a production environment as it might leak which statements are being logged to the user.
pgaudit.log_parameter	17	Specifies that audit logging should include the parameters that were passed with the statement. When parameters are present they will be be included in CSV format after the statement text.
pgaudit.log_parameter_max_size	17	Specifies, in bytes, the maximum length of variable-length parameters to log. If 0 (the default), parameters aren't checked for size. If set, when the size of the parameter is longer than the setting, the value in the audit log is replaced with a placeholder. For character types, the length is in bytes for the parameter's encoding, not characters.
pgaudit.log_relation	17	Specifies whether session audit logging should create a separate log entry for each relation referenced in a SELECT or DML statement. This is a useful shortcut for exhaustive logging without using object audit logging.
pgaudit.log_rows	17	Specifies whether logging will include the rows retrieved or affected by a statement.
pgaudit.log_statement	17	Specifies whether logging will include the statement text and parameters. Depending on requirements, the full statement text might not be required in the audit log.
pgaudit.log_statement_once	17	Specifies whether logging will include the statement text and parameters with the first log entry for a statement/substatement combination or with every entry. Disabling this setting will result in less verbose logging but might make it more difficult to determine the statement that generated a log entry, though the statement/substatement pair along with the process id should suffice to identify the statement text logged with a previous entry.
pgaudit.role	17	Specifies the master role to use for object audit logging. Multiple audit roles can be defined by granting them to the master role. This allows multiple groups to be in charge of different aspects of audit logging.
pg_hint_plan.debug_print	17	Logs results of hint parsing.
pg_hint_plan.enable_hint	17	Force planner to use plans specified in the hint comment preceding to the query.
pg_hint_plan.enable_hint_table	17	Let pg_hint_plan look up the hint table.
pg_hint_plan.message_level	17	Message level of debug messages.
pg_hint_plan.parse_messages	17	Message level of parse errors.
pglogical.batch_inserts	17	Tells PGLogical to use batch insert mechanism if possible.
pglogical.conflict_log_level	17	Sets the log level for reporting detected conflicts when the pglogical.conflict_resolution is set to anything else than error.
pglogical.conflict_resolution	17	Sets the resolution method for any detected conflicts between local data and incoming changes.
pglogical.extra_connection_options	17	connection options to add to all peer node connections.
pglogical.synchronous_commit	17	pglogical specific synchronous commit value.
pglogical.temp_directory	17	Directory to store dumps for local restore.
pglogical.use_spi	17	Tells PGLogical to use SPI interface to form actual SQL (INSERT, UPDATE, DELETE) statements to apply incoming changes instead of using internal low level interface.
pgms_stats.is_enabled_fs	17	Internal Use Only: This parameter is used as a feature override switch.
pgms_wait_sampling.history_period	17	Sets the the frequency, in milliseconds, at which wait events are sampled.
pgms_wait_sampling.is_enabled_fs	17	Internal Use Only: This parameter is used as a feature override switch. If it shows as off, wait sampling will be disabled despite the value set for pgms_wait_sampling.query_capture_mode.
pgms_wait_sampling.query_capture_mode	17	Selects types of wait events are tracked by this extension. Need to reload the config to make change take effect.
pg_partman_bgw.analyze	17	Whether to run an analyze on a partition set whenever a new partition is created during run_maintenance(). Set to 'on' to send TRUE (default). Set to 'off' to send FALSE.
pg_partman_bgw.dbname	17	CSV list of specific databases in the cluster to run pg_partman BGW on.
pg_partman_bgw.interval	17	How often run_maintenance() is called (in seconds).
pg_partman_bgw.jobmon	17	Whether to log run_maintenance() calls to pg_jobmon if it's installed. Set to 'on' to send TRUE (default). Set to 'off' to send FALSE.
pg_partman_bgw.maintenance_wait	17	How long to wait between each partition set when running maintenance (in seconds).
pg_partman_bgw.role	17	Role to be used by BGW. Must have execute permissions on run_maintenance().
pg_prewarm.autoprewarm	17	Starts the autoprewarm worker.
pg_prewarm.autoprewarm_interval	17	Sets the interval between dumps of shared buffers. If set to zero, time-based dumping is disabled.
pg_qs.interval_length_minutes	17	Sets the aggregration window in minutes. Need to reload the config to make change take effect.
pg_qs.max_captured_queries	17	Specifies the number of most relevant queries for which query store captures runtime statistics at each interval.
pg_qs.max_plan_size	17	Sets the maximum number of bytes that will be saved for query plan text; longer plans will be truncated. Need to reload the config for this change to take effect.
pg_qs.max_query_text_length	17	Sets the maximum query text length that will be saved; longer queries will be truncated. Need to reload the config to make change take effect.
pg_qs.parameters_capture_mode	17	Selects how positional query parameters are captured by pg_qs. Need to reload the config for the change to take effect.
pg_qs.query_capture_mode	17	Selects which statements are tracked by pg_qs. Need to reload the config to make change take effect.
pg_qs.retention_period_in_days	17	Sets the retention period window in days for pg_qs - after this time data will be deleted. Need to restart the server to make change take effect.
pg_qs.store_query_plans	17	Turns saving query plans on or off. Need to reload the config for the change to take effect.
pg_qs.track_utility	17	Selects whether utility commands are tracked by pg_qs. Need to reload the config to make change take effect.
pg_stat_statements.max	17	Sets the maximum number of statements tracked by pg_stat_statements.
pg_stat_statements.save	17	Save pg_stat_statements statistics across server shutdowns.
pg_stat_statements.track	17	Selects which statements are tracked by pg_stat_statements.
pg_stat_statements.track_planning	17	Selects whether planning duration is tracked by pg_stat_statements.
pg_stat_statements.track_utility	17	Selects whether utility commands are tracked by pg_stat_statements.
postgis.gdal_enabled_drivers	17	Controls postgis GDAL enabled driver settings.
squeeze.max_xlock_time	17	The maximum time the processed table might be locked exclusively. The source table is locked exclusively during the final stage of processing. If the lock time should exceed this value, the lock is released and the final stage is retried a few more times.
squeeze.worker_autostart	17	Names of databases for which background workers start automatically. Comma-separated list for of databases which squeeze worker starts as soon as the cluster startup has completed.
squeeze.worker_role	17	Role that background workers use to connect to database. If background worker was launched automatically on cluster startup, it uses this role to initiate database connection(s).
squeeze.workers_per_database	17	Maximum number of squeeze worker processes launched for each database.
timescaledb.bgw_launcher_poll_time	17	Launcher timeout value in milliseconds. Configure the time the launcher waits to look for new TimescaleDB instances.
timescaledb.disable_load	17	Disable the loading of the actual extension.
timescaledb.max_background_workers	17	Maximum background worker processes allocated to TimescaleDB. Max background worker processes allocated to TimescaleDB - set to at least 1 + number of databases in Postgres instance to use background workers.
timescaledb_osm.disable_load	17	Disable the loading of the actual extension.

Developer Options

Name	Versions	Description
allow_in_place_tablespaces	17	Allows tablespaces directly inside pg_tblspc, for testing.
allow_system_table_mods	17	Allows modifications of the structure of system tables.
backtrace_functions	17	Log backtrace for errors in these functions.
debug_discard_caches	17	Aggressively flush system caches for debugging purposes.
debug_io_direct	17	Use direct I/O for file access.
debug_logical_replication_streaming	17	Forces immediate streaming or serialization of changes in large transactions. On the publisher, it allows streaming or serializing each change in logical decoding. On the subscriber, it allows serialization of all changes to files and notifies the parallel apply workers to read and apply them at the end of the transaction.
debug_parallel_query	17	Forces the planner's use parallel query nodes. This can be useful for testing the parallel query infrastructure by forcing the planner to generate plans that contain nodes that perform tuple communication between workers and the main process.
ignore_checksum_failure	17	Continues processing after a checksum failure. Detection of a checksum failure normally causes PostgreSQL to report an error, aborting the current transaction. Setting ignore_checksum_failure to true causes the system to ignore the failure (but still report a warning), and continue processing. This behavior could cause crashes or other serious problems. Only has an effect if checksums are enabled.
ignore_invalid_pages	17	Continues recovery after an invalid pages failure. Detection of WAL records having references to invalid pages during recovery causes PostgreSQL to raise a PANIC-level error, aborting the recovery. Setting "ignore_invalid_pages" to true causes the system to ignore invalid page references in WAL records (but still report a warning), and continue recovery. This behavior might cause crashes, data loss, propagate or hide corruption, or other serious problems. Only has an effect during recovery or in standby mode.
ignore_system_indexes	17	Disables reading from system indexes. It doesn't prevent updating the indexes, so it's safe to use. The worst consequence is slowness.
jit_debugging_support	17	Register JIT-compiled functions with debugger.
jit_dump_bitcode	17	Write out LLVM bitcode to facilitate JIT debugging.
jit_expressions	17	Allow JIT compilation of expressions.
jit_profiling_support	17	Register JIT-compiled functions with perf profiler.
jit_tuple_deforming	17	Allow JIT compilation of tuple deforming.
post_auth_delay	17	Sets the amount of time to wait after authentication on connection startup. This allows attaching a debugger to the process.
pre_auth_delay	17	Sets the amount of time to wait before authentication on connection startup. This allows attaching a debugger to the process.
remove_temp_files_after_crash	17	Remove temporary files after backend crash.
send_abort_for_crash	17	Send SIGABRT not SIGQUIT to child processes after backend crash.
send_abort_for_kill	17	Send SIGABRT not SIGKILL to stuck child processes.
trace_connection_negotiation	17	Logs details of pre-authentication connection handshake.
trace_notify	17	Generates debugging output for LISTEN and NOTIFY.
trace_sort	17	Emit information about resource usage in sorting.
wal_consistency_checking	17	Sets the WAL resource managers for which WAL consistency checks are done. Full-page images will be logged for all data blocks and cross-checked against the results of WAL replay.
zero_damaged_pages	17	Continues processing past damaged page headers. 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.

Error Handling

Name	Versions	Description
data_sync_retry	17	Whether to continue running after a failure to sync data files.
exit_on_error	17	Terminate session on any error.
recovery_init_sync_method	17	Sets the method for synchronizing the data directory before crash recovery.
restart_after_crash	17	Reinitialize server after backend crash.

File Locations

Name	Versions	Description
config_file	17	Sets the server's main configuration file.
data_directory	17	Sets the server's data directory.
external_pid_file	17	Writes the postmaster PID to the specified file.
hba_file	17	Sets the server's "hba" configuration file.
ident_file	17	Sets the server's "ident" configuration file.

Intelligent Tuning

Name	Versions	Description
index_tuning.analysis_interval	17	Sets the frequency at which each index optimization session is triggered when index_tuning.mode is set to 'REPORT'.
index_tuning.max_columns_per_index	17	Maximum number of columns that can be part of the index key for any recommended index.
index_tuning.max_index_count	17	Maximum number of indexes that can be recommended for each database during one optimization session.
index_tuning.max_indexes_per_table	17	Maximum number of indexes that can be recommended for each table.
index_tuning.max_queries_per_database	17	Number of slowest queries per database for which indexes can be recommended.
index_tuning.max_regression_factor	17	Acceptable regression introduced by a recommended index on any of the queries analyzed during one optimization session.
index_tuning.max_total_size_factor	17	Maximum total size, in percentage of total disk space, that all recommended indexes for any given database can use.
index_tuning.min_improvement_factor	17	Cost improvement that a recommended index must provide to at least one of the queries analyzed during one optimization session.
index_tuning.mode	17	Configures index optimization as disabled ('OFF') or enabled to only emit recommendation. Requires Query Store to be enabled by setting pg_qs.query_capture_mode to 'TOP' or 'ALL'.
index_tuning.unused_dml_per_table	17	Minimum number of daily average DML operations affecting the table, so that their unused indexes are considered for dropping.
index_tuning.unused_min_period	17	Minimum number of days the index hasn't been used, based on system statistics, so that it's considered for dropping.
index_tuning.unused_reads_per_table	17	Minimum number of daily average read operations affecting the table, so that their unused indexes are considered for dropping.
intelligent_tuning	17	Enables intelligent tuning
intelligent_tuning.metric_targets	17	Specifies which metrics will be adjusted by intelligent tuning.
logfiles.download_enable	17	Enables or disables server logs functionality.
logfiles.retention_days	17	Sets the retention period window in days for server logs - after this time data will be deleted.

Lock Management

Name	Versions	Description
deadlock_timeout	17	Sets the time to wait on a lock before checking for deadlock.
max_locks_per_transaction	17	Sets the maximum number of locks per transaction. The shared lock table is sized on the assumption that at most "max_locks_per_transaction" objects per server process or prepared transaction will need to be locked at any one time.
max_pred_locks_per_page	17	Sets the maximum number of predicate-locked tuples per page. If more than this number of tuples on the same page are locked by a connection, those locks are replaced by a page-level lock.
max_pred_locks_per_relation	17	Sets the maximum number of predicate-locked pages and tuples per relation. If more than this total of pages and tuples in the same relation are locked by a connection, those locks are replaced by a relation-level lock.
max_pred_locks_per_transaction	17	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" objects per server process or prepared transaction will need to be locked at any one time.

Metrics

Name	Versions	Description
metrics.autovacuum_diagnostics	17	Enables metrics collection for all table statistics within a database
metrics.collector_database_activity	17	Enables metrics collection for database and activity statistics
metrics.pgbouncer_diagnostics	17	Enables metrics collection for PgBouncer.

Migration

Name	Versions	Description
azure.migration_copy_with_binary	17	When set to on, this parameter will enable the use of the binary format for copying data during migration.
azure.migration_skip_analyze	17	When set to on, this parameter will skip the analyze phase (vacuumdb --analyze-only) during the migration.
azure.migration_skip_extensions	17	When set to on, this parameter will skip the migration of extensions.
azure.migration_skip_large_objects	17	When set to on, this parameter will skip the migration of large objects such as BLOBs.
azure.migration_skip_role_user	17	When set to on, this parameter will exclude user roles from the migration process.
azure.migration_table_split_size	17	When set, this parameter specifies the size at which tables will be partitioned during migration.

PgBouncer

Name	Versions	Description
pgbouncer.default_pool_size	17	How many server connections to allow per user/database pair.
pgbouncer.enabled	17	Denotes if pgBouncer service is enabled.
pgbouncer.ignore_startup_parameters	17	Comma-separated list of parameters that PgBouncer can ignore because they are going to be handled by the admin.
pgbouncer.max_client_conn	17	Maximum number of client connections allowed.
pgbouncer.max_prepared_statements	17	When this is set to a non-zero value PgBouncer tracks protocol-level named prepared statements related commands sent by the client in transaction and statement pooling mode.
pgbouncer.min_pool_size	17	Add more server connections to pool if below this number.
pgbouncer.pool_mode	17	Specifies when a server connection can be reused by other clients.
pgbouncer.query_wait_timeout	17	Maximum time (in seconds) queries are allowed to spend waiting for execution. If the query isn't assigned to a server during that time, the client is disconnected.
pgbouncer.server_idle_timeout	17	If a server connection has been idle more than this many seconds it will be dropped. If 0 then timeout is disabled.
pgbouncer.stats_users	17	Comma-separated list of database users that are allowed to connect and run read-only queries on the pgBouncer console.

Preset Options

Name	Versions	Description
block_size	17	Shows the size of a disk block.
data_checksums	17	Shows whether data checksums are turned on for this cluster.
data_directory_mode	17	Shows the mode of the data directory. The parameter value is 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).).
debug_assertions	17	Shows whether the running server has assertion checks enabled.
huge_pages_status	17	Indicates the status of huge pages.
in_hot_standby	17	Shows whether hot standby is currently active.
integer_datetimes	17	Shows whether datetimes are integer based.
max_function_args	17	Shows the maximum number of function arguments.
max_identifier_length	17	Shows the maximum identifier length.
max_index_keys	17	Shows the maximum number of index keys.
segment_size	17	Shows the number of pages per disk file.
server_encoding	17	Shows the server (database) character set encoding.
server_version	17	Shows the server version.
server_version_num	17	Shows the server version as an integer.
shared_memory_size	17	Shows the size of the server's main shared memory area (rounded up to the nearest MB).
shared_memory_size_in_huge_pages	17	Shows the number of huge pages needed for the main shared memory area. -1 indicates that the value couldn't be determined.
ssl_library	17	Shows the name of the SSL library.
wal_block_size	17	Shows the block size in the write ahead log.
wal_segment_size	17	Shows the size of write ahead log segments.

Process Title

Name	Versions	Description
cluster_name	17	Sets the name of the cluster, which is included in the process title.
update_process_title	17	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.

Query Tuning / Genetic Query Optimizer

Name	Versions	Description
geqo	17	Enables genetic query optimization. This algorithm attempts to do planning without exhaustive searching.
geqo_effort	17	GEQO: effort is used to set the default for other GEQO parameters.
geqo_generations	17	GEQO: number of iterations of the algorithm. Zero selects a suitable default value.
geqo_pool_size	17	GEQO: number of individuals in the population. Zero selects a suitable default value.
geqo_seed	17	GEQO: seed for random path selection.
geqo_selection_bias	17	GEQO: selective pressure within the population.
geqo_threshold	17	Sets the threshold of FROM items beyond which GEQO is used.

Query Tuning / Other Planner Options

Name	Versions	Description
constraint_exclusion	17	Enables the planner to use constraints to optimize queries. Table scans will be skipped if their constraints guarantee that no rows match the query.
cursor_tuple_fraction	17	Sets the planner's estimate of the fraction of a cursor's rows that will be retrieved.
default_statistics_target	17	Sets the default statistics target. This applies to table columns that haven't had a column-specific target set via ALTER TABLE SET STATISTICS.
from_collapse_limit	17	Sets the FROM-list size beyond which subqueries aren't collapsed. The planner will merge subqueries into upper queries if the resulting FROM list would have no more than this many items.
jit	17	Allow JIT compilation.
join_collapse_limit	17	Sets the FROM-list size beyond which JOIN constructs aren't 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.
plan_cache_mode	17	Controls the planner's selection of custom or generic plan. Prepared statements can have custom and generic plans, and the planner will attempt to choose which is better. This can be set to override the default behavior.
recursive_worktable_factor	17	Sets the planner's estimate of the average size of a recursive query's working table.

Query Tuning / Planner Cost Constants

Name	Versions	Description
cpu_index_tuple_cost	17	Sets the planner's estimate of the cost of processing each index entry during an index scan.
cpu_operator_cost	17	Sets the planner's estimate of the cost of processing each operator or function call.
cpu_tuple_cost	17	Sets the planner's estimate of the cost of processing each tuple (row).
effective_cache_size	17	Sets the planner's assumption about the total size of the data caches. That is, the total size of the caches (kernel cache and shared buffers) used for PostgreSQL data files. This is measured in disk pages, which are normally 8 kB each.
jit_above_cost	17	Perform JIT compilation if query is more expensive. -1 disables JIT compilation.
jit_inline_above_cost	17	Perform JIT inlining if query is more expensive. -1 disables inlining.
jit_optimize_above_cost	17	Optimize JIT-compiled functions if query is more expensive. -1 disables optimization.
min_parallel_index_scan_size	17	Sets the minimum amount of index data for a parallel scan. If the planner estimates that it will read a number of index pages too small to reach this limit, a parallel scan will not be considered.
min_parallel_table_scan_size	17	Sets the minimum amount of table data for a parallel scan. If the planner estimates that it will read a number of table pages too small to reach this limit, a parallel scan will not be considered.
parallel_setup_cost	17	Sets the planner's estimate of the cost of starting up worker processes for parallel query.
parallel_tuple_cost	17	Sets the planner's estimate of the cost of passing each tuple (row) from worker to leader backend.
random_page_cost	17	Sets the planner's estimate of the cost of a nonsequentially fetched disk page.
seq_page_cost	17	Sets the planner's estimate of the cost of a sequentially fetched disk page.

Query Tuning / Planner Method Configuration

Name	Versions	Description
enable_async_append	17	Enables the planner's use of async append plans.
enable_bitmapscan	17	Enables the planner's use of bitmap-scan plans.
enable_gathermerge	17	Enables the planner's use of gather merge plans.
enable_group_by_reordering	17	Enables reordering of GROUP BY keys.
enable_hashagg	17	Enables the planner's use of hashed aggregation plans.
enable_hashjoin	17	Enables the planner's use of hash join plans.
enable_incremental_sort	17	Enables the planner's use of incremental sort steps.
enable_indexonlyscan	17	Enables the planner's use of index-only-scan plans.
enable_indexscan	17	Enables the planner's use of index-scan plans.
enable_material	17	Enables the planner's use of materialization.
enable_memoize	17	Enables the planner's use of memoization.
enable_mergejoin	17	Enables the planner's use of merge join plans.
enable_nestloop	17	Enables the planner's use of nested-loop join plans.
enable_parallel_append	17	Enables the planner's use of parallel append plans.
enable_parallel_hash	17	Enables the planner's use of parallel hash plans.
enable_partition_pruning	17	Enables plan-time and execution-time partition pruning. Allows the query planner and executor to compare partition bounds to conditions in the query to determine which partitions must be scanned.
enable_partitionwise_aggregate	17	Enables partitionwise aggregation and grouping.
enable_partitionwise_join	17	Enables partitionwise join.
enable_presorted_aggregate	17	Enables the planner's ability to produce plans that provide presorted input for ORDER BY / DISTINCT aggregate functions. Allows the query planner to build plans that provide presorted input for aggregate functions with an ORDER BY / DISTINCT clause. When disabled, implicit sorts are always performed during execution.
enable_seqscan	17	Enables the planner's use of sequential-scan plans.
enable_sort	17	Enables the planner's use of explicit sort steps.
enable_tidscan	17	Enables the planner's use of TID scan plans.

Replication / Master Server

Name	Versions	Description
synchronous_standby_names	17	Number of synchronous standbys and list of names of potential synchronous ones.

Replication / Sending Servers

Name	Versions	Description
max_replication_slots	17	Sets the maximum number of simultaneously defined replication slots.
max_slot_wal_keep_size	17	Sets the maximum WAL size that can be reserved by replication slots. Replication slots will be marked as failed, and segments released for deletion or recycling, if this much space is occupied by WAL on disk.
max_wal_senders	17	Sets the maximum number of simultaneously running WAL sender processes.
track_commit_timestamp	17	Collects transaction commit time.
wal_keep_size	17	Sets the size of WAL files held for standby servers.
wal_sender_timeout	17	Sets the maximum time to wait for WAL replication.

Replication / Standby Servers

Name	Versions	Description
hot_standby	17	Allows connections and queries during recovery.
hot_standby_feedback	17	Allows feedback from a hot standby to the primary that will avoid query conflicts.
max_standby_archive_delay	17	Sets the maximum delay before canceling queries when a hot standby server is processing archived WAL data.
max_standby_streaming_delay	17	Sets the maximum delay before canceling queries when a hot standby server is processing streamed WAL data.
primary_conninfo	17	Sets the connection string to be used to connect to the sending server.
primary_slot_name	17	Sets the name of the replication slot to use on the sending server.
recovery_min_apply_delay	17	Sets the minimum delay for applying changes during recovery.
synchronized_standby_slots	17	Lists streaming replication standby server replication slot names that logical WAL sender processes will wait for. Logical WAL sender processes will send decoded changes to output plugins only after the specified replication slots have confirmed receiving WAL.
sync_replication_slots	17	Enables a physical standby to synchronize logical failover replication slots from the primary server.
wal_receiver_create_temp_slot	17	Sets whether a WAL receiver should create a temporary replication slot if no permanent slot is configured.
wal_receiver_status_interval	17	Sets the maximum interval between WAL receiver status reports to the sending server.
wal_receiver_timeout	17	Sets the maximum wait time to receive data from the sending server.
wal_retrieve_retry_interval	17	Sets the time to wait before retrying to retrieve WAL after a failed attempt.

Replication / Subscribers

Name	Versions	Description
max_logical_replication_workers	17	Maximum number of logical replication worker processes.
max_parallel_apply_workers_per_subscription	17	Maximum number of parallel apply workers per subscription.
max_sync_workers_per_subscription	17	Maximum number of table synchronization workers per subscription.

Reporting and Logging / What to Log

Name	Versions	Description
application_name	17	Sets the application name to be reported in statistics and logs.
debug_pretty_print	17	Indents parse and plan tree displays.
debug_print_parse	17	Logs each query's parse tree.
debug_print_plan	17	Logs each query's execution plan.
debug_print_rewritten	17	Logs each query's rewritten parse tree.
log_autovacuum_min_duration	17	Sets the minimum execution time above which autovacuum actions will be logged. Zero prints all actions. -1 turns autovacuum logging off.
log_checkpoints	17	Logs each checkpoint.
log_connections	17	Logs each successful connection.
log_disconnections	17	Logs end of a session, including duration.
log_duration	17	Logs the duration of each completed SQL statement.
log_error_verbosity	17	Sets the verbosity of logged messages.
log_hostname	17	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	17	Controls information prefixed to each log line. If blank, no prefix is used.
log_lock_waits	17	Logs long lock waits.
log_parameter_max_length	17	Sets the maximum length in bytes of data logged for bind parameter values when logging statements. -1 to print values in full.
log_parameter_max_length_on_error	17	Sets the maximum length in bytes of data logged for bind parameter values when logging statements, on error. -1 to print values in full.
log_recovery_conflict_waits	17	Logs standby recovery conflict waits.
log_replication_commands	17	Logs each replication command.
log_statement	17	Sets the type of statements logged.
log_temp_files	17	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	17	Sets the time zone to use in log messages.

Reporting and Logging / When to Log

Name	Versions	Description
log_min_duration_sample	17	Sets the minimum execution time above which a sample of statements will be logged. Sampling is determined by log_statement_sample_rate. Zero logs a sample of all queries. -1 turns this feature off.
log_min_duration_statement	17	Sets the minimum execution time above which all statements will be logged. Zero prints all queries. -1 turns this feature off.
log_min_error_statement	17	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	17	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_startup_progress_interval	17	Time between progress updates for long-running startup operations. 0 turns this feature off.
log_statement_sample_rate	17	Fraction of statements exceeding "log_min_duration_sample" to be logged. Use a value between 0.0 (never log) and 1.0 (always log).
log_transaction_sample_rate	17	Sets the fraction of transactions from which to log all statements. Use a value between 0.0 (never log) and 1.0 (log all statements for all transactions).

Reporting and Logging / Where to Log

Name	Versions	Description
event_source	17	Sets the application name used to identify PostgreSQL messages in the event log.
log_destination	17	Sets the destination for server log output. Valid values are combinations of "stderr", "syslog", "csvlog", "jsonlog", and "eventlog", depending on the platform.
log_directory	17	Sets the destination directory for log files. Can be specified as relative to the data directory or as absolute path.
log_file_mode	17	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	17	Sets the file name pattern for log files.
logging_collector	17	Start a subprocess to capture stderr, csvlog and/or jsonlog into log files.
log_rotation_age	17	Sets the amount of time to wait before forcing log file rotation.
log_rotation_size	17	Sets the maximum size a log file can reach before being rotated.
log_truncate_on_rotation	17	Truncate existing log files of same name during log rotation.
syslog_facility	17	Sets the syslog "facility" to be used when syslog enabled.
syslog_ident	17	Sets the program name used to identify PostgreSQL messages in syslog.
syslog_sequence_numbers	17	Add sequence number to syslog messages to avoid duplicate suppression.
syslog_split_messages	17	Split messages sent to syslog by lines and to fit into 1024 bytes.

Resource Usage / Asynchronous Behavior

Name	Versions	Description
backend_flush_after	17	Number of pages after which previously performed writes are flushed to disk.
effective_io_concurrency	17	Number of simultaneous requests that can be handled efficiently by the disk subsystem.
maintenance_io_concurrency	17	A variant of "effective_io_concurrency" that is used for maintenance work.
max_notify_queue_pages	17	Sets the maximum number of allocated pages for NOTIFY / LISTEN queue.
max_parallel_maintenance_workers	17	Sets the maximum number of parallel processes per maintenance operation.
max_parallel_workers	17	Sets the maximum number of parallel workers that can be active at one time.
max_parallel_workers_per_gather	17	Sets the maximum number of parallel processes per executor node.
max_worker_processes	17	Maximum number of concurrent worker processes.
parallel_leader_participation	17	Controls whether Gather and Gather Merge also run subplans. Should gather nodes also run subplans or just gather tuples?.

Resource Usage / Background Writer

Name	Versions	Description
bgwriter_delay	17	Background writer sleep time between rounds.
bgwriter_flush_after	17	Number of pages after which previously performed writes are flushed to disk.
bgwriter_lru_maxpages	17	Background writer maximum number of LRU pages to flush per round.
bgwriter_lru_multiplier	17	Multiple of the average buffer usage to free per round.

Resource Usage / Cost-Based Vacuum Delay

Name	Versions	Description
vacuum_cost_delay	17	Vacuum cost delay in milliseconds.
vacuum_cost_limit	17	Vacuum cost amount available before napping.
vacuum_cost_page_dirty	17	Vacuum cost for a page dirtied by vacuum.
vacuum_cost_page_hit	17	Vacuum cost for a page found in the buffer cache.
vacuum_cost_page_miss	17	Vacuum cost for a page not found in the buffer cache.

Resource Usage / Disk

Name	Versions	Description
temp_file_limit	17	Limits the total size of all temporary files used by each process. -1 means no limit.

Resource Usage / Kernel Resources

Name	Versions	Description
max_files_per_process	17	Sets the maximum number of simultaneously open files for each server process.

Resource Usage / Memory

Name	Versions	Description
autovacuum_work_mem	17	Sets the maximum memory to be used by each autovacuum worker process.
commit_timestamp_buffers	17	Sets the size of the dedicated buffer pool used for the commit timestamp cache. Specify 0 to have this value determined as a fraction of shared_buffers.
dynamic_shared_memory_type	17	Selects the dynamic shared memory implementation used.
hash_mem_multiplier	17	Multiple of "work_mem" to use for hash tables.
huge_pages	17	Use of huge pages on Linux or Windows.
huge_page_size	17	The size of huge page that should be requested.
io_combine_limit	17	Limit on the size of data reads and writes.
logical_decoding_work_mem	17	Sets the maximum memory to be used for logical decoding. This much memory can be used by each internal reorder buffer before spilling to disk.
maintenance_work_mem	17	Sets the maximum memory to be used for maintenance operations. This includes operations such as VACUUM and CREATE INDEX.
max_prepared_transactions	17	Sets the maximum number of simultaneously prepared transactions.
max_stack_depth	17	Sets the maximum stack depth, in kilobytes.
min_dynamic_shared_memory	17	Amount of dynamic shared memory reserved at startup.
multixact_member_buffers	17	Sets the size of the dedicated buffer pool used for the MultiXact member cache.
multixact_offset_buffers	17	Sets the size of the dedicated buffer pool used for the MultiXact offset cache.
notify_buffers	17	Sets the size of the dedicated buffer pool used for the LISTEN/NOTIFY message cache.
serializable_buffers	17	Sets the size of the dedicated buffer pool used for the serializable transaction cache.
shared_buffers	17	Sets the number of shared memory buffers used by the server.
shared_memory_type	17	Selects the shared memory implementation used for the main shared memory region.
subtransaction_buffers	17	Sets the size of the dedicated buffer pool used for the subtransaction cache. Specify 0 to have this value determined as a fraction of shared_buffers.
temp_buffers	17	Sets the maximum number of temporary buffers used by each session.
transaction_buffers	17	Sets the size of the dedicated buffer pool used for the transaction status cache. Specify 0 to have this value determined as a fraction of shared_buffers.
vacuum_buffer_usage_limit	17	Sets the buffer pool size for VACUUM, ANALYZE, and autovacuum.
work_mem	17	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.

Statistics / Cumulative Query and Index Statistics

Name	Versions	Description
stats_fetch_consistency	17	Sets the consistency of accesses to statistics data.
track_activities	17	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	17	Sets the size reserved for pg_stat_activity.query, in bytes.
track_counts	17	Collects statistics on database activity.
track_functions	17	Collects function-level statistics on database activity.
track_io_timing	17	Collects timing statistics for database I/O activity.
track_wal_io_timing	17	Collects timing statistics for WAL I/O activity.

Statistics / Monitoring

Name	Versions	Description
compute_query_id	17	Enables in-core computation of query identifiers.
log_executor_stats	17	Writes executor performance statistics to the server log.
log_parser_stats	17	Writes parser performance statistics to the server log.
log_planner_stats	17	Writes planner performance statistics to the server log.
log_statement_stats	17	Writes cumulative performance statistics to the server log.

TLS

Name	Versions	Description
require_secure_transport	17	Whether client connections to the server are required to use some form of secure transport.

Version and Platform Compatibility / Other Platforms and Clients

Name	Versions	Description
allow_alter_system	17	Allows running the ALTER SYSTEM command. Can be set to off for environments where global configuration changes should be made using a different method.
transform_null_equals	17	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).

Version and Platform Compatibility / Previous PostgreSQL Versions

Name	Versions	Description
array_nulls	17	Enable input of NULL elements in arrays. When turned on, unquoted NULL in an array input value means a null value; otherwise it's taken literally.
backslash_quote	17	Sets whether "\'" is allowed in string literals.
escape_string_warning	17	Warn about backslash escapes in ordinary string literals.
lo_compat_privileges	17	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.
quote_all_identifiers	17	When generating SQL fragments, quote all identifiers.
standard_conforming_strings	17	Causes '...' strings to treat backslashes literally.
synchronize_seqscans	17	Enable synchronized sequential scans.

Write-Ahead Log / Archive Recovery

Name	Versions	Description
archive_cleanup_command	17	Sets the shell command that will be executed at every restart point.
recovery_end_command	17	Sets the shell command that will be executed once at the end of recovery.
restore_command	17	Sets the shell command that will be called to retrieve an archived WAL file.

Write-Ahead Log / Archiving

Name	Versions	Description
archive_command	17	Sets the shell command that will be called to archive a WAL file. This is used only if "archive_library" isn't set.
archive_library	17	Sets the library that will be called to archive a WAL file. An empty string indicates that "archive_command" should be used.
archive_mode	17	Allows archiving of WAL files using "archive_command".
archive_timeout	17	Sets the amount of time to wait before forcing a switch to the next WAL file.

Write-Ahead Log / Checkpoints

Name	Versions	Description
checkpoint_completion_target	17	Time spent flushing dirty buffers during checkpoint, as fraction of checkpoint interval.
checkpoint_flush_after	17	Number of pages after which previously performed writes are flushed to disk.
checkpoint_timeout	17	Sets the maximum time between automatic WAL checkpoints.
checkpoint_warning	17	Sets the maximum time before warning if checkpoints triggered by WAL volume happen too frequently. Write a message to the server log if checkpoints caused by the filling of WAL segment files happen more frequently than this amount of time. Zero turns off the warning.
max_wal_size	17	Sets the WAL size that triggers a checkpoint.
min_wal_size	17	Sets the minimum size to shrink the WAL to.

Write-Ahead Log / Recovery

Name	Versions	Description
recovery_prefetch	17	Prefetch referenced blocks during recovery. Look ahead in the WAL to find references to uncached data.
wal_decode_buffer_size	17	Buffer size for reading ahead in the WAL during recovery. Maximum distance to read ahead in the WAL to prefetch referenced data blocks.

Write-Ahead Log / Recovery Target

Name	Versions	Description
recovery_target	17	Set to "immediate" to end recovery as soon as a consistent state is reached.
recovery_target_action	17	Sets the action to perform upon reaching the recovery target.
recovery_target_inclusive	17	Sets whether to include or exclude transaction with recovery target.
recovery_target_lsn	17	Sets the LSN of the write-ahead log location up to which recovery will proceed.
recovery_target_name	17	Sets the named restore point up to which recovery will proceed.
recovery_target_time	17	Sets the time stamp up to which recovery will proceed.
recovery_target_timeline	17	Specifies the timeline to recover into.
recovery_target_xid	17	Sets the transaction ID up to which recovery will proceed.
summarize_wal	17	Starts the WAL summarizer process to enable incremental backup.

Write-Ahead Log / Settings

Name	Versions	Description
commit_delay	17	Sets the delay in microseconds between transaction commit and flushing WAL to disk.
commit_siblings	17	Sets the minimum number of concurrent open transactions required before performing "commit_delay".
fsync	17	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 ensures that a database cluster will recover to a consistent state after an operating system or hardware crash.
full_page_writes	17	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 aren't enough to recover. This option writes pages when first modified after a checkpoint to WAL so full recovery is possible.
synchronous_commit	17	Sets the current transaction's synchronization level.
wal_buffers	17	Sets the number of disk-page buffers in shared memory for WAL. Specify -1 to have this value determined as a fraction of shared_buffers.
wal_compression	17	Compresses full-page writes written in WAL file.
wal_init_zero	17	Writes zeroes to new WAL files before first use.
wal_level	17	Sets the level of information written to the WAL.
wal_log_hints	17	Writes full pages to WAL when first modified after a checkpoint, even for a non-critical modification.
wal_recycle	17	Recycles WAL files by renaming them.
wal_skip_threshold	17	Minimum size of new file to fsync instead of writing WAL.
wal_summary_keep_time	17	Time for which WAL summary files should be kept.
wal_sync_method	17	Selects the method used for forcing WAL updates to disk.
wal_writer_delay	17	Time between WAL flushes performed in the WAL writer.
wal_writer_flush_after	17	Amount of WAL written out by WAL writer that triggers a flush.

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