update performance

tidb-lightning/tidb-lightning-configuration.md

@@ -134,9 +134,9 @@ driver = "file"
 #              You can manually insert the correct records into the target table based on your application requirements. Note that the target TiKV must be v5.2.0 or later versions.
 # - "ignore": when encountering conflicting primary or unique key records, TiDB Lightning retains the old data and ignores the new data. This option can only be used in the logical import mode.
 strategy = ""
-# Controls whether to enable preprocess conflict detection, which checks conflicts in data before importing it to TiDB. The default value is false, indicating that TiDB Lightning only checks conflicts after the import. If you set it to true, TiDB Lightning checks conflicts both before and after the import. This parameter can be used only in the physical import mode. It is not recommended to set `precheck-conflict-before-import = true` for now.
+# Controls whether to enable preprocess conflict detection, which checks conflicts in data before importing it to TiDB. The default value is false, indicating that TiDB Lightning only checks conflicts after the import. If you set it to true, TiDB Lightning checks conflicts both before and after the import. This parameter can be used only in the physical import mode. In scenarios where the number of conflict records is greater than 1,000,000, it is recommended to set `precheck-conflict-before-import = true` for better performance in conflict detection. In other scenarios, it is recommended to disable it.
 # precheck-conflict-before-import = false
-# Controls the maximum number of conflict errors that can be handled when strategy is "replace" or "ignore". You can set it only when strategy is "replace" or "ignore". The default value is 10000. If you set the value larger than 10000, it is possible that the import will have performance degradation or fail due to potential errors. 
+# Controls the maximum number of conflict errors that can be handled when strategy is "replace" or "ignore". You can set it only when strategy is "replace" or "ignore". The default value is 10000. If you set the value larger than 10000, it is possible that the import will experience performance degradation. 
 # threshold = 10000
 # Controls the maximum number of records in the `conflict_records` table. The default value is 10000. 
 # Starting from v8.1.0, there is no need to configure `max-record-rows` manually, because TiDB Lightning automatically assigns the value of `max-record-rows` with the value of `threshold`, regardless of the user input. `max-record-rows` will be deprecated in a future release.

tidb-lightning/tidb-lightning-physical-import-mode-usage.md

@@ -38,7 +38,7 @@ data-source-dir = "/data/my_database"
 #              If you set `conflict.strategy = "replace"` in physical import mode, the conflicting data can be checked in the `lightning_task_info.conflict_view` view.
 #              You can manually insert the correct records into the target table based on your application requirements. Note that the target TiKV must be v5.2.0 or later versions.
 strategy = ""
-# Controls whether to enable preprocess conflict detection, which checks conflicts in data before importing it to TiDB. In scenarios where the ratio of conflict records is greater than or equal to 1%, it is recommended to set `precheck-conflict-before-import = true` for better performance in conflict detection. In other scenarios, it is recommended to disable it. The default value is false, indicating that TiDB Lightning only checks conflicts after the import. If you set it to true, TiDB Lightning checks conflicts both before and after the import.
+# Controls whether to enable preprocess conflict detection, which checks conflicts in data before importing it to TiDB. The default value is false, indicating that TiDB Lightning only checks conflicts after the import. If you set it to true, TiDB Lightning checks conflicts both before and after the import. This parameter can be used only in the physical import mode. In scenarios where the number of conflict records is greater than 1,000,000, it is recommended to set `precheck-conflict-before-import = true` for better performance in conflict detection. In other scenarios, it is recommended to disable it.
 # precheck-conflict-before-import = false
 # threshold = 10000
 # Starting from v8.1.0, there is no need to configure `max-record-rows` manually, because TiDB Lightning automatically assigns the value of `max-record-rows` with the value of `threshold`, regardless of the user input. `max-record-rows` will be deprecated in a future release.