Update ticdc-changefeed-config.md

Author: hfxsd

ticdc/ticdc-changefeed-config.md

@@ -165,7 +165,7 @@ For more information, see [Event filter rules](/ticdc/ticdc-filter.md#event-filt
 
 #### `region-count-per-span` <span class="version-mark">New in v8.5.4</span>
 
-- During changefeed initialization, tables that meet the split conditions are split according to this parameter. After splitting, each split sub-table contains at most `region-count-per-span` Regions.
+- Introduced in the [TiCDC new architecture](/ticdc/ticdc-architecture.md). During changefeed initialization, tables that meet the split conditions are split according to this parameter. After splitting, each split sub-table contains at most `region-count-per-span` Regions.
 - Default value: `100` 
 
 #### `region-threshold`