MySQL 5.7 Reference Manual Including MySQL NDB Cluster 7.5 and NDB Cluster 7.6
The threads
table provides information about
threads running in the NDB
kernel.
The threads
table contains the following
columns:
node_id
ID of the node where the thread is running
thr_no
Thread ID (specific to this node)
thread_name
Thread name (type of thread)
thread_description
Thread (type) description
Sample output from a 2-node example cluster, including thread descriptions, is shown here:
mysql> SELECT * FROM threads;
+---------+--------+-------------+------------------------------------------------------------------+
| node_id | thr_no | thread_name | thread_description |
+---------+--------+-------------+------------------------------------------------------------------+
| 5 | 0 | main | main thread, schema and distribution handling |
| 5 | 1 | rep | rep thread, asynch replication and proxy block handling |
| 5 | 2 | ldm | ldm thread, handling a set of data partitions |
| 5 | 3 | recv | receive thread, performing receive and polling for new receives |
| 6 | 0 | main | main thread, schema and distribution handling |
| 6 | 1 | rep | rep thread, asynch replication and proxy block handling |
| 6 | 2 | ldm | ldm thread, handling a set of data partitions |
| 6 | 3 | recv | receive thread, performing receive and polling for new receives |
+---------+--------+-------------+------------------------------------------------------------------+
8 rows in set (0.01 sec)
This table was added in NDB 7.5.2.