update MD by dispatch event pingcap/docs release-cloud

Author: github-actions

markdown-pages/en/tidbcloud/master/tidb-cloud/serverless-export.md

@@ -13,6 +13,10 @@ While you can also export data using tools such as [mysqldump](https://dev.mysql
 - Isolation: the export service uses separate computing resources, ensuring isolation from the resources used by your online services.
 - Consistency: the export service ensures the consistency of the exported data without causing locks, which does not affect your online services.
 
+> **Note:**
+>
+> The maximum export size is currently 1 TiB. To export more data or request a higher export speed, contact [TiDB Cloud Support](/tidb-cloud/tidb-cloud-support.md).
+
 ## Export locations
 
 You can export data to the following locations:
@@ -410,6 +414,17 @@ ticloud serverless export cancel -c <cluster-id> -e <export-id>
 </div>
 </SimpleTab>
 
+## Export speed
+
+The export speed depends on your [cluster plan](/tidb-cloud/select-cluster-tier.md):
+
+- **TiDB Cloud Starter**:
+
+    - If the spending limit is set to 0, the export speed is up to 25 MiB/s.
+    - If the spending limit is greater than 0, the export speed is up to 100 MiB/s.
+
+- **TiDB Cloud Essential**: up to 100 MiB/s.
+
 ## Pricing
 
 The export service is free during the beta period. You only need to pay for the [Request Units (RUs)](/tidb-cloud/tidb-cloud-glossary.md#request-unit) generated during the export process of successful or canceled tasks. For failed export tasks, you will not be charged.