Performance Schema table_lock_waits_summary_by_table Table

The table_lock_waits_summary_by_table table records table lock waits by table.

Column Description
OBJECT_TYPE Since this table records waits by table, always set to TABLE.
OBJECT_SCHEMA Schema name.
OBJECT_NAME Table name.
COUNT_STAR Number of summarized events and the sum of the x_READ and x_WRITE columns.
SUM_TIMER_WAIT Total wait time of the summarized events that are timed.
MIN_TIMER_WAIT Minimum wait time of the summarized events that are timed.
AVG_TIMER_WAIT Average wait time of the summarized events that are timed.
MAX_TIMER_WAIT Maximum wait time of the summarized events that are timed.
COUNT_READ Number of all read operations, and the sum of the equivalent x_READ_NORMAL, x_READ_WITH_SHARED_LOCKS, x_READ_HIGH_PRIORITY and x_READ_NO_INSERT columns.
SUM_TIMER_READ Total wait time of all read operations that are timed.
MIN_TIMER_READ Minimum wait time of all read operations that are timed.
AVG_TIMER_READ Average wait time of all read operations that are timed.
MAX_TIMER_READ Maximum wait time of all read operations that are timed.
COUNT_WRITE Number of all write operations, and the sum of the equivalent x_WRITE_ALLOW_WRITE, x_WRITE_CONCURRENT_INSERT, x_WRITE_DELAYED, x_WRITE_LOW_PRIORITY and x_WRITE_NORMAL columns.
SUM_TIMER_WRITE Total wait time of all write operations that are timed.
MIN_TIMER_WRITE Minimum wait time of all write operations that are timed.
AVG_TIMER_WRITE Average wait time of all write operations that are timed.
MAX_TIMER_WRITE Maximum wait time of all write operations that are timed.
COUNT_READ_NORMAL Number of all internal read normal locks.
SUM_TIMER_READ_NORMAL Total wait time of all internal read normal locks that are timed.
MIN_TIMER_READ_NORMAL Minimum wait time of all internal read normal locks that are timed.
AVG_TIMER_READ_NORMAL Average wait time of all internal read normal locks that are timed.
MAX_TIMER_READ_NORMAL Maximum wait time of all internal read normal locks that are timed.
COUNT_READ_WITH_SHARED_LOCKS Number of all internal read with shared locks.
SUM_TIMER_READ_WITH_SHARED_LOCKS Total wait time of all internal read with shared locks that are timed.
MIN_TIMER_READ_WITH_SHARED_LOCKS Minimum wait time of all internal read with shared locks that are timed.
AVG_TIMER_READ_WITH_SHARED_LOCKS Average wait time of all internal read with shared locks that are timed.
MAX_TIMER_READ_WITH_SHARED_LOCKS Maximum wait time of all internal read with shared locks that are timed.
COUNT_READ_HIGH_PRIORITY Number of all internal read high priority locks.
SUM_TIMER_READ_HIGH_PRIORITY Total wait time of all internal read high priority locks that are timed.
MIN_TIMER_READ_HIGH_PRIORITY Minimum wait time of all internal read high priority locks that are timed.
AVG_TIMER_READ_HIGH_PRIORITY Average wait time of all internal read high priority locks that are timed.
MAX_TIMER_READ_HIGH_PRIORITY Maximum wait time of all internal read high priority locks that are timed.
COUNT_READ_NO_INSERT Number of all internal read no insert locks.
SUM_TIMER_READ_NO_INSERT Total wait time of all internal read no insert locks that are timed.
MIN_TIMER_READ_NO_INSERT Minimum wait time of all internal read no insert locks that are timed.
AVG_TIMER_READ_NO_INSERT Average wait time of all internal read no insert locks that are timed.
MAX_TIMER_READ_NO_INSERT Maximum wait time of all internal read no insert locks that are timed.
COUNT_READ_EXTERNAL Number of all external read locks.
SUM_TIMER_READ_EXTERNAL Total wait time of all external read locks that are timed.
MIN_TIMER_READ_EXTERNAL Minimum wait time of all external read locks that are timed.
AVG_TIMER_READ_EXTERNAL Average wait time of all external read locks that are timed.
MAX_TIMER_READ_EXTERNAL Maximum wait time of all external read locks that are timed.
COUNT_WRITE_ALLOW_WRITE Number of all internal read normal locks.
SUM_TIMER_WRITE_ALLOW_WRITE Total wait time of all internal write allow write locks that are timed.
MIN_TIMER_WRITE_ALLOW_WRITE Minimum wait time of all internal write allow write locks that are timed.
AVG_TIMER_WRITE_ALLOW_WRITE Average wait time of all internal write allow write locks that are timed.
MAX_TIMER_WRITE_ALLOW_WRITE Maximum wait time of all internal write allow write locks that are timed.
COUNT_WRITE_CONCURRENT_INSERT Number of all internal concurrent insert write locks.
SUM_TIMER_WRITE_CONCURRENT_INSERT Total wait time of all internal concurrent insert write locks that are timed.
MIN_TIMER_WRITE_CONCURRENT_INSERT Minimum wait time of all internal concurrent insert write locks that are timed.
AVG_TIMER_WRITE_CONCURRENT_INSERT Average wait time of all internal concurrent insert write locks that are timed.
MAX_TIMER_WRITE_CONCURRENT_INSERT Maximum wait time of all internal concurrent insert write locks that are timed.
COUNT_WRITE_DELAYED Number of all internal write delayed locks.
SUM_TIMER_WRITE_DELAYED Total wait time of all internal write delayed locks that are timed.
MIN_TIMER_WRITE_DELAYED Minimum wait time of all internal write delayed locks that are timed.
AVG_TIMER_WRITE_DELAYED Average wait time of all internal write delayed locks that are timed.
MAX_TIMER_WRITE_DELAYED Maximum wait time of all internal write delayed locks that are timed.
COUNT_WRITE_LOW_PRIORITY Number of all internal write low priority locks.
SUM_TIMER_WRITE_LOW_PRIORITY Total wait time of all internal write low priority locks that are timed.
MIN_TIMER_WRITE_LOW_PRIORITY Minimum wait time of all internal write low priority locks that are timed.
AVG_TIMER_WRITE_LOW_PRIORITY Average wait time of all internal write low priority locks that are timed.
MAX_TIMER_WRITE_LOW_PRIORITY Maximum wait time of all internal write low priority locks that are timed.
COUNT_WRITE_NORMAL Number of all internal write normal locks.
SUM_TIMER_WRITE_NORMAL Total wait time of all internal write normal locks that are timed.
MIN_TIMER_WRITE_NORMAL Minimum wait time of all internal write normal locks that are timed.
AVG_TIMER_WRITE_NORMAL Average wait time of all internal write normal locks that are timed.
MAX_TIMER_WRITE_NORMAL Maximum wait time of all internal write normal locks that are timed.
COUNT_WRITE_EXTERNAL Number of all external write locks.
SUM_TIMER_WRITE_EXTERNAL Total wait time of all external write locks that are timed.
MIN_TIMER_WRITE_EXTERNAL Minimum wait time of all external write locks that are timed.
AVG_TIMER_WRITE_EXTERNAL Average wait time of all external write locks that are timed.
MAX_TIMER_WRITE_EXTERNAL Maximum wait time of all external write locks that are timed.

You can TRUNCATE the table, which will reset all counters to zero.

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