v7.5.1: tikv configuration doc: add gc thread number (#16564) (#16632)

releases/release-7.6.0.md

@@ -284,7 +284,7 @@ Quick access: [Quick start](https://docs.pingcap.com/tidb/v7.6/quick-start-with-
 | TiKV | [`blob-file-compression`](/tikv-configuration-file.md#blob-file-compression) | Modified | The algorithm used for compressing values in Titan, which takes value as the unit. Starting from TiDB v7.6.0, the default compression algorithm is `zstd`. |
 | TiKV | [`rocksdb.defaultcf.titan.min-blob-size`](/tikv-configuration-file.md#min-blob-size) | Modified   | Starting from TiDB v7.6.0, the default value for new clusters is `32KB`. For existing clusters upgrading to v7.6.0, the default value `1KB` remains unchanged. |
 | TiKV | [`rocksdb.titan.enabled`](/tikv-configuration-file.md#enabled) | Modified  |  Enables or disables Titan. For v7.5.0 and earlier versions, the default value is `false`. Starting from v7.6.0, the default value is `true` for only new clusters. Existing clusters upgraded to v7.6.0 or later versions will retain the original configuration. |
-| TiKV | [`gc.num-threads`](/tikv-configuration-file.md#num-threads-new-in-v658-and-v760) | Newly added | When `enable-compaction-filter` is set to `false`, this parameter controls the number of GC threads. The default value is `1`. |
+| TiKV | [`gc.num-threads`](/tikv-configuration-file.md#num-threads-new-in-v658-v751-and-v760) | Newly added | When `enable-compaction-filter` is set to `false`, this parameter controls the number of GC threads. The default value is `1`. |
 | TiKV | [`raftstore.periodic-full-compact-start-times`](/tikv-configuration-file.md#periodic-full-compact-start-times-new-in-v760) | Newly added | Sets the specific times that TiKV initiates periodic full compaction. The default value `[]` means periodic full compaction is disabled. |
 | TiKV | [`raftstore.periodic-full-compact-start-max-cpu`](/tikv-configuration-file.md#periodic-full-compact-start-max-cpu-new-in-v760) | Newly added | Limits the maximum CPU usage rate for TiKV periodic full compaction. The default value is `0.1`. |
 | TiKV | [`zstd-dict-size`](/tikv-configuration-file.md#zstd-dict-size) |  Newly added | Specifies the `zstd` dictionary compression size. The default value is `"0KB"`, which means to disable the `zstd` dictionary compression. |

tikv-configuration-file.md

@@ -2065,7 +2065,7 @@ Configuration items related to TiDB Lightning import and BR restore.
 + The garbage ratio threshold to trigger GC.
 + Default value: `1.1`
 
-### `num-threads` <span class="version-mark">New in v6.5.8 and v7.6.0</span>
+### `num-threads` <span class="version-mark">New in v6.5.8, v7.5.1, and v7.6.0</span>
 
 + The number of GC threads when `enable-compaction-filter` is `false`.
 + Default value: `1`