10.16.3 The tp_thread_state Table

Note

The Performance Schema table described here is available as of MySQL 8.0.14. Prior to MySQL 8.0.14, use the corresponding INFORMATION_SCHEMA table instead; see The INFORMATION_SCHEMA TP_THREAD_STATE Table.

The tp_thread_state table has one row per thread created by the thread pool to handle connections.

The tp_thread_state table has these columns:

• TP_GROUP_ID

  The thread group ID.

• TP_THREAD_NUMBER

  The ID of the thread within its thread group. TP_GROUP_ID and TP_THREAD_NUMBER together provide a unique key within the table.

• PROCESS_COUNT

  The 10ms interval in which the statement that uses this thread is currently executing. 0 means no statement is executing, 1 means it is in the first 10ms, and so forth.

• WAIT_TYPE

  The type of wait for the thread. NULL means the thread is not blocked. Otherwise, the thread is blocked by a call to thd_wait_begin() and the value specifies the type of wait. The xxx_WAIT columns of the tp_thread_group_stats table accumulate counts for each wait type.

  The WAIT_TYPE value is a string that describes the type of wait, as shown in the following table.

  Table 10.6 tp_thread_state Table WAIT_TYPE Values

  Wait Type	Meaning
  THD_WAIT_SLEEP	Waiting for sleep
  THD_WAIT_DISKIO	Waiting for Disk IO
  THD_WAIT_ROW_LOCK	Waiting for row lock
  THD_WAIT_GLOBAL_LOCK	Waiting for global lock
  THD_WAIT_META_DATA_LOCK	Waiting for metadata lock
  THD_WAIT_TABLE_LOCK	Waiting for table lock
  THD_WAIT_USER_LOCK	Waiting for user lock
  THD_WAIT_BINLOG	Waiting for binlog
  THD_WAIT_GROUP_COMMIT	Waiting for group commit
  THD_WAIT_SYNC	Waiting for fsync

  
  

• TP_THREAD_TYPE

  The type of thread. The value shown in this column is one of CONNECTION_HANDLER_WORKER_THREAD, LISTENER_WORKER_THREAD, QUERY_WORKER_THREAD, or TIMER_WORKER_THREAD.

  This column was added in MySQL 8.0.32.

• THREAD_ID

  This thread's unique identifier. The value is the same as that used in the THREAD_ID column of the Performance Schema threads table.

  This column was added in MySQL 8.0.32.

The tp_thread_state table has these indexes:

• Unique index on (TP_GROUP_ID, TP_THREAD_NUMBER)

TRUNCATE TABLE is not permitted for the tp_thread_state table.