PostgreSQL 18 → 19 Beta 3 GUC diff

Core configuration parameters added, removed, or changed in boot default between PostgreSQL 18 and 19 Beta 3.

Note

Fact. The measured inventory changes from 399 to 419 settings: 22 added, 6 boot-default changes, and 2 removed.

Added parameters

Parameter	Type	Context	Boot default	Category
`autovacuum_analyze_score_weight`	`real`	`sighup`	`1`	Vacuuming / Automatic Vacuuming
`autovacuum_freeze_score_weight`	`real`	`sighup`	`1`	Vacuuming / Automatic Vacuuming
`autovacuum_max_parallel_workers`	`integer`	`sighup`	`0`	Vacuuming / Automatic Vacuuming
`autovacuum_multixact_freeze_score_weight`	`real`	`sighup`	`1`	Vacuuming / Automatic Vacuuming
`autovacuum_vacuum_insert_score_weight`	`real`	`sighup`	`1`	Vacuuming / Automatic Vacuuming
`autovacuum_vacuum_score_weight`	`real`	`sighup`	`1`	Vacuuming / Automatic Vacuuming
`debug_exec_backend`	`bool`	`internal`	`off`	Preset Options
`debug_print_raw_parse`	`bool`	`user`	`off`	Reporting and Logging / What to Log
`effective_wal_level`	`enum`	`internal`	`replica`	Preset Options
`enable_eager_aggregate`	`bool`	`user`	`on`	Query Tuning / Planner Method Configuration
`hosts_file`	`string`	`postmaster`	— (not set)	File Locations
`io_max_workers`	`integer`	`sighup`	`8`	Resource Usage / I/O
`io_min_workers`	`integer`	`sighup`	`2`	Resource Usage / I/O
`io_worker_idle_timeout`	`integer`	`sighup`	`60000 ms` (1 min)	Resource Usage / I/O
`io_worker_launch_interval`	`integer`	`sighup`	`100 ms`	Resource Usage / I/O
`log_autoanalyze_min_duration`	`integer`	`sighup`	`600000 ms` (10 min)	Reporting and Logging / What to Log
`max_repack_replication_slots`	`integer`	`postmaster`	`5`	Replication / Sending Servers
`min_eager_agg_group_size`	`real`	`user`	`8`	Query Tuning / Planner Cost Constants
`password_expiration_warning_threshold`	`integer`	`sighup`	`604800 s` (7 d)	Connections and Authentication / Authentication
`ssl_sni`	`bool`	`sighup`	`off`	Connections and Authentication / SSL
`timing_clock_source`	`enum`	`superuser`	`auto`	Resource Usage / Time
`wal_sender_shutdown_timeout`	`integer`	`user`	`-1 ms`	Replication / Sending Servers

Boot-default changes

Parameter	PG18	PG19 Beta 3	Category
`default_toast_compression`	`pglz`	`lz4`	Client Connection Defaults / Statement Behavior
`jit`	`on`	`off`	Query Tuning / Other Planner Options
`log_lock_waits`	`off`	`on`	Reporting and Logging / What to Log
`max_locks_per_transaction`	`64`	`128`	Lock Management
`server_version`	`18.6 (Debian 18.6-1.pgdg13+2)`	`19beta3 (Debian 19~beta3-1.pgdg13+1)`	Preset Options
`server_version_num`	`180006`	`190000`	Preset Options

Removed parameters

Parameter	Last type	Context	Last boot default	Category
`escape_string_warning`	`bool`	`user`	`on`	Version and Platform Compatibility / Previous PostgreSQL Versions
`io_workers`	`integer`	`sighup`	`3`	Resource Usage / I/O

Method

The three lists compare the pinned PG18 and PG19 Beta 3 pg_settings snapshots directly. A default change is a change in the boot_val plus unit pair; setting is excluded so an initdb-generated value is not mistaken for the compiled boot default.