innodb_transactions_summary

NAME

innodb_transactions_summary: A one line summary of InnoDB's transactions: count, state, locks

TYPE

View

DESCRIPTION

innodb_transactions_summary provides a quick summary of InnoDB Plugin's current transactions state: number of running transactions, of which how many are executing or locked, on how many locks.

The connection calling upon this view is never listed.

STRUCTURE

mysql> DESC common_schema.innodb_transactions_summary;
+----------------------+---------------+------+-----+---------+-------+
| Field                | Type          | Null | Key | Default | Extra |
+----------------------+---------------+------+-----+---------+-------+
| count_transactions   | bigint(21)    | NO   |     | 0       |       |
| running_transactions | decimal(23,0) | NO   |     | 0       |       |
| locked_transactions  | decimal(23,0) | NO   |     | 0       |       |
| distinct_locks       | bigint(21)    | NO   |     | 0       |       |
+----------------------+---------------+------+-----+---------+-------+

SYNOPSIS

Columns of this view:

  • count_transactions: number of current transactions
  • running_transactions: number of transactions executing a query
  • locked_transactions: number of transactions waiting on some lock
  • distinct_locks: number of distinct locks transactions are waiting on, or 0 when no transaction is locked

EXAMPLES

Get transactions summary:

mysql> SELECT * FROM common_schema.innodb_transactions_summary;
+--------------------+----------------------+---------------------+----------------+
| count_transactions | running_transactions | locked_transactions | distinct_locks |
+--------------------+----------------------+---------------------+----------------+
|                  9 |                    7 |                   2 |              2 |
+--------------------+----------------------+---------------------+----------------+

In the above server, 9 transactions are open, of which 7 are executing a query (the other two are "in between queries"). Of the 7 executing queries, 5 are running normally, but 2 are blocked.

ENVIRONMENT

MySQL 5.1 with InnoDB Plugin installed (with InnoDB INFORMATION_SCHEMA plugins enabled), or MySQL >= 5.5

SEE ALSO

innodb_locked_transactions, innodb_simple_locks, innodb_transactions

AUTHOR

Shlomi Noach
 
common_schema documentation