# PostgreSQL 14 → 15 GUC 差异

> PG14 与 PG15 之间新增、boot 默认值变化和移除的核心配置参数。
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> [!NOTE]
> **Fact。** 实测在档数从 348 变为 355；新增 8、boot 默认值变化 6、移除 1。

## 新增参数 {#added}

| 参数 | 类型 | Context | Boot 默认值 | 分类 |
| --- | --- | --- | --- | --- |
| [`archive_library`](/zh/parameters/archive-library/) | `string` | `sighup` | `""` (empty string) | Write-Ahead Log / Archiving |
| [`log_startup_progress_interval`](/zh/parameters/log-startup-progress-interval/) | `integer` | `sighup` | `10000 ms` (10 s) | Reporting and Logging / When to Log |
| [`recovery_prefetch`](/zh/parameters/recovery-prefetch/) | `enum` | `sighup` | `try` | Write-Ahead Log / Recovery |
| [`recursive_worktable_factor`](/zh/parameters/recursive-worktable-factor/) | `real` | `user` | `10` | Query Tuning / Other Planner Options |
| [`shared_memory_size`](/zh/parameters/shared-memory-size/) | `integer` | `internal` | `0 MB` (0 B) | Preset Options |
| [`shared_memory_size_in_huge_pages`](/zh/parameters/shared-memory-size-in-huge-pages/) | `integer` | `internal` | `-1` | Preset Options |
| [`stats_fetch_consistency`](/zh/parameters/stats-fetch-consistency/) | `enum` | `user` | `cache` | Statistics / Cumulative Query and Index Statistics |
| [`wal_decode_buffer_size`](/zh/parameters/wal-decode-buffer-size/) | `integer` | `postmaster` | `524288 B` (512 KiB) | Write-Ahead Log / Recovery |
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## Boot 默认值变化 {#default-changes}

| 参数 | PG14 | PG15 | 分类 |
| --- | --- | --- | --- |
| [`hash_mem_multiplier`](/zh/parameters/hash-mem-multiplier/) | `1` | `2` | Resource Usage / Memory |
| [`log_autovacuum_min_duration`](/zh/parameters/log-autovacuum-min-duration/) | `-1 ms` | `600000 ms` (10 min) | Reporting and Logging / What to Log |
| [`log_checkpoints`](/zh/parameters/log-checkpoints/) | `off` | `on` | Reporting and Logging / What to Log |
| [`server_version`](/zh/parameters/server-version/) | `14.24 (Debian 14.24-1.pgdg13+2)` | `15.19 (Debian 15.19-1.pgdg13+2)` | Preset Options |
| [`server_version_num`](/zh/parameters/server-version-num/) | `140024` | `150019` | Preset Options |
| [`shared_buffers`](/zh/parameters/shared-buffers/) | `1024 8kB` (8 MiB (1024 × 8kB)) | `16384 8kB` (128 MiB (16384 × 8kB)) | Resource Usage / Memory |
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## 移除参数 {#removed}

| 参数 | 最后类型 | Context | 最后 Boot 默认值 | 分类 |
| --- | --- | --- | --- | --- |
| [`stats_temp_directory`](/zh/parameters/stats-temp-directory/) | `string` | `sighup` | `pg_stat_tmp` | Statistics / Query and Index Statistics Collector |
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## 计算方法 {#method}

三张清单直接比较固定环境中的 PG14 与 PG15 `pg_settings` 快照。默认值变化使用 `boot_val` 与 `unit` 的组合；`setting` 不参与判定，以免把 `initdb` 生成值误当作编译时默认值。

- [机器可读差异数据](/data/diffs.json)
- [完整 GUC JSONL](/data/guc.jsonl)