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- 问题分类：内容太简略、描述不清有歧义、步骤不完整
- 出现的页面：链接+截图
- 出现的问题：
https://docs.pingcap.com/zh/tidb/stable/tidb-configuration-file#instance
下列参数没有文档说明？
ddl_slow_threshold
plugin_dir
plugin_load
tidb_check_mb4_value_in_utf8
tidb_expensive_txn_time_threshold
tidb_general_log
tidb_pprof_sql_cpu
tidb_rc_read_check_ts
tidb_service_scope
mysql> select version();
+--------------------+
| version() |
+--------------------+
| 8.0.11-TiDB-v7.5.0 |
+--------------------+
1 row in set (0.01 sec)
mysql> select * from information_schema.cluster_config where `key` like 'instance.%';
+------+-------------------+----------------------------------------------+---------------------+
| TYPE | INSTANCE | KEY | VALUE |
+------+-------------------+----------------------------------------------+---------------------+
| tidb | 192.168.8.92:4000 | instance.ddl_slow_threshold | 300 |
| tidb | 192.168.8.92:4000 | instance.max_connections | 0 |
| tidb | 192.168.8.92:4000 | instance.plugin_dir | /data/deploy/plugin |
| tidb | 192.168.8.92:4000 | instance.plugin_load | |
| tidb | 192.168.8.92:4000 | instance.tidb_check_mb4_value_in_utf8 | true |
| tidb | 192.168.8.92:4000 | instance.tidb_enable_collect_execution_info | true |
| tidb | 192.168.8.92:4000 | instance.tidb_enable_ddl | true |
| tidb | 192.168.8.92:4000 | instance.tidb_enable_slow_log | true |
| tidb | 192.168.8.92:4000 | instance.tidb_expensive_query_time_threshold | 60 |
| tidb | 192.168.8.92:4000 | instance.tidb_expensive_txn_time_threshold | 600 |
| tidb | 192.168.8.92:4000 | instance.tidb_force_priority | NO_PRIORITY |
| tidb | 192.168.8.92:4000 | instance.tidb_general_log | false |
| tidb | 192.168.8.92:4000 | instance.tidb_pprof_sql_cpu | false |
| tidb | 192.168.8.92:4000 | instance.tidb_rc_read_check_ts | false |
| tidb | 192.168.8.92:4000 | instance.tidb_record_plan_in_slow_log | 1 |
| tidb | 192.168.8.92:4000 | instance.tidb_service_scope | |
| tidb | 192.168.8.92:4000 | instance.tidb_slow_log_threshold | 300 |
| tidb | 192.168.8.92:4000 | instance.tidb_stmt_summary_enable_persistent | false |
| tidb | 192.168.8.92:4000 | instance.tidb_stmt_summary_file_max_backups | 0 |
| tidb | 192.168.8.92:4000 | instance.tidb_stmt_summary_file_max_days | 3 |
| tidb | 192.168.8.92:4000 | instance.tidb_stmt_summary_file_max_size | 64 |
| tidb | 192.168.8.92:4000 | instance.tidb_stmt_summary_filename | tidb-statements.log |
+------+-------------------+----------------------------------------------+---------------------+
22 rows in set (0.03 sec)