PostgreSQL 14 → 15 GUC diff

Core configuration parameters added, removed, or changed in boot default between PostgreSQL 14 and 15.

Note

Fact. The measured inventory changes from 348 to 355 settings: 8 added, 6 boot-default changes, and 1 removed.

Added parameters

Parameter	Type	Context	Boot default	Category
`archive_library`	`string`	`sighup`	`""` (empty string)	Write-Ahead Log / Archiving
`log_startup_progress_interval`	`integer`	`sighup`	`10000 ms` (10 s)	Reporting and Logging / When to Log
`recovery_prefetch`	`enum`	`sighup`	`try`	Write-Ahead Log / Recovery
`recursive_worktable_factor`	`real`	`user`	`10`	Query Tuning / Other Planner Options
`shared_memory_size`	`integer`	`internal`	`0 MB` (0 B)	Preset Options
`shared_memory_size_in_huge_pages`	`integer`	`internal`	`-1`	Preset Options
`stats_fetch_consistency`	`enum`	`user`	`cache`	Statistics / Cumulative Query and Index Statistics
`wal_decode_buffer_size`	`integer`	`postmaster`	`524288 B` (512 KiB)	Write-Ahead Log / Recovery

Boot-default changes

Parameter	PG14	PG15	Category
`hash_mem_multiplier`	`1`	`2`	Resource Usage / Memory
`log_autovacuum_min_duration`	`-1 ms`	`600000 ms` (10 min)	Reporting and Logging / What to Log
`log_checkpoints`	`off`	`on`	Reporting and Logging / What to Log
`server_version`	`14.24 (Debian 14.24-1.pgdg13+2)`	`15.19 (Debian 15.19-1.pgdg13+2)`	Preset Options
`server_version_num`	`140024`	`150019`	Preset Options
`shared_buffers`	`1024 8kB` (8 MiB (1024 × 8kB))	`16384 8kB` (128 MiB (16384 × 8kB))	Resource Usage / Memory

Removed parameters

Parameter	Last type	Context	Last boot default	Category
`stats_temp_directory`	`string`	`sighup`	`pg_stat_tmp`	Statistics / Query and Index Statistics Collector

Method

The three lists compare the pinned PG14 and PG15 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.