> For the complete documentation index, see [llms.txt](https://docs.greennode.ai/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.greennode.ai/vdb/relational-database-service-rds/postgresql-standalone/config-parameters-for-standalone.md). # Parameters for PostgreSQL Standalone This page lists the parameters that can be customized through a **DB Configuration Group** when using vDB PostgreSQL Standalone (Single Node). {% hint style="info" %} * **Restart Required** = Yes: Changing this parameter requires a **restart** of the database instance to take effect. * **Restart Required** = No: Changes are applied immediately without a restart. * All parameters listed are modifiable. {% endhint %} *** ## Parameter List by Version The parameter list for PostgreSQL versions **13, 14, and 15** is **identical**. Versions **10** and **12** support additional parameters (see [the section below](#additional-parameters-for-postgresql-10-and-12)). *** ### Checkpoints & WAL | Parameter | Allowed Values | Type | Restart Required | | ---------------------- | -------------- | ------- | ---------------- | | `checkpoint_timeout` | 30 - 3600 | integer | No | | `checkpoint_warning` | 0 - 2147483647 | integer | No | | `commit_delay` | 0 - 100000 | integer | No | | `commit_siblings` | 0 - 1000 | integer | No | | `wal_buffers` | -1 - 262143 | integer | **Yes** | | `wal_keep_size` | 0 - 2147483647 | integer | No | | `wal_receiver_timeout` | 0 - 3600000 | integer | No | | `wal_sender_timeout` | 0 - 3600000 | integer | No | ### Connections & Authentication | Parameter | Allowed Values | Type | Restart Required | | ------------------------------------- | -------------- | ------- | ---------------- | | `idle_in_transaction_session_timeout` | 0 - 2147483647 | integer | No | | `max_connections` | 11 - 65536 | integer | **Yes** | | `tcp_keepalives_count` | 0 - 2147483647 | integer | No | | `tcp_keepalives_idle` | 0 - 2147483647 | integer | No | | `tcp_keepalives_interval` | 0 - 2147483647 | integer | No | ### Memory & Buffers | Parameter | Allowed Values | Type | Restart Required | | ---------------------- | ---------------- | ------- | ---------------- | | `effective_cache_size` | 1 - 2147483647 | integer | No | | `shared_buffers` | 16 - 1073741823 | integer | **Yes** | | `temp_buffers` | 100 - 1073741823 | integer | No | | `work_mem` | 64 - 10485760 | integer | No | ### Query Planning & Optimization | Parameter | Allowed Values | Type | Restart Required | | --------------------------- | ------------------ | ------- | ---------------- | | `constraint_exclusion` | partition, on, off | string | No | | `default_statistics_target` | 1 - 10000 | integer | No | | `force_parallel_mode` | true / false | boolean | No | | `from_collapse_limit` | 1 - 2147483647 | integer | No | | `geqo` | true / false | boolean | No | | `geqo_effort` | 1 - 10 | integer | No | | `geqo_generations` | 0 - 1000 | integer | No | | `geqo_pool_size` | 0 - 1000 | integer | No | | `geqo_threshold` | 2 - 2147483647 | integer | No | | `join_collapse_limit` | 1 - 2147483647 | integer | No | | `replacement_sort_tuples` | 0 - 2147483647 | integer | No | ### Replication & Standby | Parameter | Allowed Values | Type | Restart Required | | ---------------------- | -------------- | ------- | ---------------- | | `hot_standby_feedback` | true / false | boolean | No | | `synchronize_seqscans` | true / false | boolean | No | ### Transactions & Locking | Parameter | Allowed Values | Type | Restart Required | | -------------------------------- | --------------------------------------------------------------- | ------- | ---------------- | | `deadlock_timeout` | 1 - 2147483647 | integer | No | | `default_transaction_deferrable` | true / false | boolean | No | | `default_transaction_isolation` | serializable, repeatable read, read committed, read uncommitted | string | No | | `lock_timeout` | 1 - 2147483647 | integer | No | | `max_locks_per_transaction` | 10 - 1000 | integer | **Yes** | | `max_pred_locks_per_transaction` | 10 - 1000 | integer | **Yes** | | `max_prepared_transactions` | 0 - 65536 | integer | **Yes** | | `max_worker_processes` | 0 - 65536 | integer | **Yes** | ### Miscellaneous | Parameter | Allowed Values | Type | Restart Required | | ----------------------------- | --------------- | ------- | ---------------- | | `gin_pending_list_limit` | 64 - 2147483647 | integer | No | | `standard_conforming_strings` | true / false | boolean | No | *** ## Additional Parameters for PostgreSQL 10 and 12 The parameters below are **only available on PostgreSQL 10 and/or 12** and are not supported on PostgreSQL 13+. ### Connections & Authentication (PG 10, 12) | Parameter | Allowed Values | Type | Restart Required | | -------------------------------- | -------------- | ------- | ---------------- | | `authentication_timeout` | 1 - 600 | integer | No | | `max_files_per_process` | 50 - 2000 | integer | **Yes** | | `statement_timeout` | 0 - 2147483647 | integer | No | | `superuser_reserved_connections` | 0 - 8388607 | integer | **Yes** | ### Memory & I/O (PG 10, 12) | Parameter | Allowed Values | Type | Restart Required | | -------------------------- | -------------- | ------- | ---------------- | | `backend_flush_after` | 0 - 256 | integer | No | | `bgwriter_delay` | 10 - 10000 | integer | No | | `bgwriter_flush_after` | 0 - 256 | integer | No | | `bgwriter_lru_maxpages` | 0 - 1000 | integer | No | | `checkpoint_flush_after` | 0 - 256 | integer | No | | `effective_io_concurrency` | 0 - 1000 | integer | No | ### Encoding & Format (PG 10, 12) | Parameter | Allowed Values | Type | Restart Required | | ----------------- | ----------------------------------------------------- | ------ | ---------------- | | `backslash_quote` | safe\_encoding, on, off | string | No | | `bytea_output` | escape, hex | string | No | | `client_encoding` | UTF8, LATIN1, ... (multiple values) | string | No | | `datestyle` | ISO, Postgres, SQL, German | string | No | | `intervalstyle` | postgres, postgres\_verbose, sql\_standard, iso\_8601 | string | No | | `xmlbinary` | base64, hex | string | No | | `xmloption` | content, document | string | No | ### WAL & Replication (PG 10, 12) | Parameter | Allowed Values | Type | Restart Required | Notes | | ------------------------------ | ---------------------- | ------- | ---------------- | -------------------------------------------------- | | `session_replication_role` | origin, replica, local | string | No | | | `synchronous_commit` | local, on, off | string | No | | | `wal_keep_segments` | 0 - 2147483647 | integer | No | PG 10 only; replaced by `wal_keep_size` from PG 12 | | `wal_receiver_status_interval` | 0 - 2147483 | integer | No | | | `wal_writer_delay` | 1 - 10000 | integer | No | | ### Boolean Flags (PG 10, 12) | Parameter | Description | Restart Required | | ------------------------------- | ------------------------------------------- | ---------------- | | `array_nulls` | Allow NULL values in arrays | No | | `check_function_bodies` | Validate function bodies at CREATE FUNCTION | No | | `default_transaction_read_only` | Default transactions to read-only | No | | `default_with_oids` | Use OIDs by default for new tables | No | | `escape_string_warning` | Warn on escape sequences in strings | No | | `exit_on_error` | Exit session on any error | No | | `fsync` | Force synchronization of data to disk | No | | `full_page_writes` | Write full pages during checkpoint | No | | `lo_compat_privileges` | Enable large object privilege compatibility | No | | `quote_all_identifiers` | Quote all identifiers | No | | `transform_null_equals` | Treat expr = NULL as expr IS NULL | No | ### Miscellaneous (PG 10, 12) | Parameter | Allowed Values | Type | Restart Required | | -------------------- | -------------- | ------- | ---------------- | | `extra_float_digits` | -15 - 3 | integer | No |