# PostgreSQL 9.6 → 10 GUC 差异

> PG9.6 与 PG10 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 263 变为 272；新增 11、boot 默认值变化 12、移除 2。

## 新增参数 {#added}

| 参数 | 类型 | Context | Boot 默认值 | 分类 |
| --- | --- | --- | --- | --- |
| [`allow_in_place_tablespaces`](/zh/parameters/allow-in-place-tablespaces/) | `bool` | `superuser` | `off` | Developer Options |
| [`enable_gathermerge`](/zh/parameters/enable-gathermerge/) | `bool` | `user` | `on` | Query Tuning / Planner Method Configuration |
| [`max_logical_replication_workers`](/zh/parameters/max-logical-replication-workers/) | `integer` | `postmaster` | `4` | Replication / Subscribers |
| [`max_parallel_workers`](/zh/parameters/max-parallel-workers/) | `integer` | `user` | `8` | Resource Usage / Asynchronous Behavior |
| [`max_pred_locks_per_page`](/zh/parameters/max-pred-locks-per-page/) | `integer` | `sighup` | `2` | Lock Management |
| [`max_pred_locks_per_relation`](/zh/parameters/max-pred-locks-per-relation/) | `integer` | `sighup` | `-2` | Lock Management |
| [`max_sync_workers_per_subscription`](/zh/parameters/max-sync-workers-per-subscription/) | `integer` | `sighup` | `2` | Replication / Subscribers |
| [`min_parallel_index_scan_size`](/zh/parameters/min-parallel-index-scan-size/) | `integer` | `user` | `64 8kB` (512 KiB (64 × 8kB)) | Query Tuning / Planner Cost Constants |
| [`min_parallel_table_scan_size`](/zh/parameters/min-parallel-table-scan-size/) | `integer` | `user` | `1024 8kB` (8 MiB (1024 × 8kB)) | Query Tuning / Planner Cost Constants |
| [`ssl_dh_params_file`](/zh/parameters/ssl-dh-params-file/) | `string` | `sighup` | `""` (empty string) | Connections and Authentication / Security and Authentication |
| [`wal_consistency_checking`](/zh/parameters/wal-consistency-checking/) | `string` | `superuser` | `""` (empty string) | Developer Options |
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## Boot 默认值变化 {#default-changes}

| 参数 | PG9.6 | PG10 | 分类 |
| --- | --- | --- | --- |
| [`hot_standby`](/zh/parameters/hot-standby/) | `off` | `on` | Replication / Standby Servers |
| [`log_directory`](/zh/parameters/log-directory/) | `pg_log` | `log` | Reporting and Logging / Where to Log |
| [`log_line_prefix`](/zh/parameters/log-line-prefix/) | `""` (empty string) | `%m [%p] ` | Reporting and Logging / What to Log |
| [`max_parallel_workers_per_gather`](/zh/parameters/max-parallel-workers-per-gather/) | `0` | `2` | Resource Usage / Asynchronous Behavior |
| [`max_replication_slots`](/zh/parameters/max-replication-slots/) | `0` | `10` | Replication / Sending Servers |
| [`max_wal_senders`](/zh/parameters/max-wal-senders/) | `0` | `10` | Replication / Sending Servers |
| [`max_wal_size`](/zh/parameters/max-wal-size/) | `64 16MB` (1 GiB (64 × 16MB)) | `1024 MB` (1 GiB) | Write-Ahead Log / Checkpoints |
| [`min_wal_size`](/zh/parameters/min-wal-size/) | `5 16MB` (80 MiB (5 × 16MB)) | `80 MB` (80 MiB) | Write-Ahead Log / Checkpoints |
| [`password_encryption`](/zh/parameters/password-encryption/) | `on` | `md5` | Connections and Authentication / Security and Authentication |
| [`server_version`](/zh/parameters/server-version/) | `9.6.24` | `10.23 (Debian 10.23-1.pgdg110+1)` | Preset Options |
| [`server_version_num`](/zh/parameters/server-version-num/) | `90624` | `100023` | Preset Options |
| [`wal_level`](/zh/parameters/wal-level/) | `minimal` | `replica` | Write-Ahead Log / Settings |
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## 移除参数 {#removed}

| 参数 | 最后类型 | Context | 最后 Boot 默认值 | 分类 |
| --- | --- | --- | --- | --- |
| [`min_parallel_relation_size`](/zh/parameters/min-parallel-relation-size/) | `integer` | `user` | `1024 8kB` (8 MiB (1024 × 8kB)) | Query Tuning / Planner Cost Constants |
| [`sql_inheritance`](/zh/parameters/sql-inheritance/) | `bool` | `user` | `on` | Version and Platform Compatibility / Previous PostgreSQL Versions |
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## 计算方法 {#method}

三张清单直接比较固定环境中的 PG9.6 与 PG10 `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)