# PostgreSQL 9.2 → 9.3 GUC 差异

> PG9.2 与 PG9.3 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 224 变为 231；新增 9、boot 默认值变化 3、移除 2。

## 新增参数 {#added}

| 参数 | 类型 | Context | Boot 默认值 | 分类 |
| --- | --- | --- | --- | --- |
| [`autovacuum_multixact_freeze_max_age`](/zh/parameters/autovacuum-multixact-freeze-max-age/) | `integer` | `postmaster` | `400000000` | Autovacuum |
| [`data_checksums`](/zh/parameters/data-checksums/) | `bool` | `internal` | `off` | Preset Options |
| [`ignore_checksum_failure`](/zh/parameters/ignore-checksum-failure/) | `bool` | `superuser` | `off` | Developer Options |
| [`lock_timeout`](/zh/parameters/lock-timeout/) | `integer` | `user` | `0 ms` | Client Connection Defaults / Statement Behavior |
| [`unix_socket_directories`](/zh/parameters/unix-socket-directories/) | `string` | `postmaster` | `/var/run/postgresql` | Connections and Authentication / Connection Settings |
| [`vacuum_multixact_freeze_min_age`](/zh/parameters/vacuum-multixact-freeze-min-age/) | `integer` | `user` | `5000000` | Client Connection Defaults / Statement Behavior |
| [`vacuum_multixact_freeze_table_age`](/zh/parameters/vacuum-multixact-freeze-table-age/) | `integer` | `user` | `150000000` | Client Connection Defaults / Statement Behavior |
| [`wal_receiver_timeout`](/zh/parameters/wal-receiver-timeout/) | `integer` | `sighup` | `60000 ms` (1 min) | Replication / Standby Servers |
| [`wal_sender_timeout`](/zh/parameters/wal-sender-timeout/) | `integer` | `sighup` | `60000 ms` (1 min) | Replication / Sending Servers |
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## Boot 默认值变化 {#default-changes}

| 参数 | PG9.2 | PG9.3 | 分类 |
| --- | --- | --- | --- |
| [`server_version`](/zh/parameters/server-version/) | `9.2.23` | `9.3.25` | Preset Options |
| [`server_version_num`](/zh/parameters/server-version-num/) | `90223` | `90325` | Preset Options |
| [`ssl_ciphers`](/zh/parameters/ssl-ciphers/) | `ALL:!ADH:!LOW:!EXP:!MD5:@STRENGTH` | `DEFAULT:!LOW:!EXP:!MD5:@STRENGTH` | Connections and Authentication / Security and Authentication |
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## 移除参数 {#removed}

| 参数 | 最后类型 | Context | 最后 Boot 默认值 | 分类 |
| --- | --- | --- | --- | --- |
| [`replication_timeout`](/zh/parameters/replication-timeout/) | `integer` | `sighup` | `60000 ms` (1 min) | Replication / Sending Servers |
| [`unix_socket_directory`](/zh/parameters/unix-socket-directory/) | `string` | `postmaster` | `""` (empty string) | Connections and Authentication / Connection Settings |
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## 计算方法 {#method}

三张清单直接比较固定环境中的 PG9.2 与 PG9.3 `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)