从 NDB 8.0.29 开始，ndbcluster插件线程在 Performance Schema threads表中可见，如以下查询所示：

mysql> SELECT name, type, thread_id, thread_os_id
    -> FROM performance_schema.threads
    -> WHERE name LIKE '%ndbcluster%'\G
+----------------------------------+------------+-----------+--------------+
| name                             | type       | thread_id | thread_os_id |
+----------------------------------+------------+-----------+--------------+
| thread/ndbcluster/ndb_binlog     | BACKGROUND |        30 |        11980 |
| thread/ndbcluster/ndb_index_stat | BACKGROUND |        31 |        11981 |
| thread/ndbcluster/ndb_metadata   | BACKGROUND |        32 |        11982 |
+----------------------------------+------------+-----------+--------------+

该threads表显示了此处列出的所有三个线程：

这些线程也在 setup_threads表中按名称显示。

线程名称使用格式 显示在和 表的name列中。 ，由引擎确定的对象类型，用于插件线程（请参阅 线程工具元素）。的是 。 是线程的独立名称（、 或 ）。 threadssetup_threadsprefix/plugin_name/thread_nameprefixperformance_schemathreadplugin_namendbclusterthread_namendb_binlogndb_index_statndb_metadata

threads使用或表 中给定线程的线程 ID 或操作系统线程 ID， setup_threads 可以从 Performance Schema 中获取有关插件执行和资源使用情况的大量信息。此示例显示如何通过连接和 表 从arena 获取ndbcluster 插件创建的线程分配的内存量：mem_rootthreadsmemory_summary_by_thread_by_event_name

mysql> SELECT
    ->   t.name,
    ->   m.sum_number_of_bytes_alloc,
    ->   IF(m.sum_number_of_bytes_alloc > 0, "true", "false") AS 'Has allocated memory'
    -> FROM performance_schema.memory_summary_by_thread_by_event_name m
    -> JOIN performance_schema.threads t
    -> ON m.thread_id = t.thread_id
    -> WHERE t.name LIKE '%ndbcluster%'
    ->   AND event_name LIKE '%THD::main_mem_root%';
+----------------------------------+---------------------------+----------------------+
| name                             | sum_number_of_bytes_alloc | Has allocated memory |
+----------------------------------+---------------------------+----------------------+
| thread/ndbcluster/ndb_binlog     |                     20576 | true                 |
| thread/ndbcluster/ndb_index_stat |                         0 | false                |
| thread/ndbcluster/ndb_metadata   |                      8240 | true                 |
+----------------------------------+---------------------------+----------------------+

从 NDB 8.0.30 开始，您可以通过查询 Performance Schema 表来查看用于事务批处理的内存量 memory_summary_by_thread_by_event_name ，类似于此处显示的内容：

mysql> SELECT EVENT_NAME
    ->   FROM performance_schema.memory_summary_by_thread_by_event_name
    ->   WHERE THREAD_ID = PS_CURRENT_THREAD_ID()
    ->     AND EVENT_NAME LIKE 'memory/ndbcluster/%';
+-------------------------------------------+
| EVENT_NAME                                |
+-------------------------------------------+
| memory/ndbcluster/Thd_ndb::batch_mem_root |
+-------------------------------------------+
1 row in set (0.01 sec)

事务ndbcluster内存工具在 Performance Schema 表中也可见 setup_instruments，如下所示：

mysql> SELECT * from performance_schema.setup_instruments 
    ->   WHERE NAME LIKE '%ndb%'\G
*************************** 1. row ***************************
         NAME: memory/ndbcluster/Thd_ndb::batch_mem_root
      ENABLED: YES
        TIMED: NULL
   PROPERTIES: 
   VOLATILITY: 0
DOCUMENTATION: Memory used for transaction batching
1 row in set (0.01 sec)