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The User Statistics feature was first released in MariaDB 5.2.0, and moved to the userstat plugin in MariaDB 10.1.1. The userstat plugin creates the USER_STATISTICS, CLIENT_STATISTICS, the INDEX_STATISTICS, and the TABLE_STATISTICS tables in the INFORMATION_SCHEMA database. As an alternative to these tables, the plugin also adds the SHOW USER_STATISTICS, the SHOW CLIENT_STATISTICS, the SHOW INDEX_STATISTICS, and the SHOW TABLE_STATISTICS statements. These tables and commands can be used to understand the server activity better and to identify the sources of your database's load. The plugin also adds the FLUSH USER_STATISTICS, FLUSH CLIENT_STATISTICS, FLUSH INDEX_STATISTICS, and FLUSH TABLE_STATISTICS statements. The MariaDB implementation of this plugin is based on the userstatv2 patch from Percona and Ourdelta. The original code comes from Google (Mark Callaghan's team) with additional work from Percona, Ourdelta, and Weldon Whipple. The MariaDB implementation provides the same functionality as the userstatv2 patch but a lot of changes have been made to make it faster and to better fit the MariaDB infrastructure. Contents How it Works Enabling the Plugin Using the Plugin Using the Information Schema Table Using the SHOW Statements Flushing Plugin Data Versions USER_STATISTICS CLIENT_STATISTICS INDEX_STATISTICS TABLE_STATISTICS System Variables userstat How it WorksThe userstat plugin works by keeping several hash tables in memory. All variables are incremented while the query is running. At the end of each statement the global values are updated. Enabling the PluginBy default statistics are not collected. This is to ensure that statistics collection does not cause any extra load on the server unless desired. Set the userstat=ON system variable in a relevant server option group in an option file to enable the plugin. For example: [mariadb] ... userstat = 1The value can also be changed dynamically. For example: SET GLOBAL userstat=1; Using the Plugin Using the Information Schema TableThe userstat plugin creates the USER_STATISTICS, CLIENT_STATISTICS, the INDEX_STATISTICS, and the TABLE_STATISTICS tables in the INFORMATION_SCHEMA database. SELECT * FROM INFORMATION_SCHEMA.USER_STATISTICS\G *************************** 1. row *************************** USER: root TOTAL_CONNECTIONS: 1 CONCURRENT_CONNECTIONS: 0 CONNECTED_TIME: 297 BUSY_TIME: 0.001725 CPU_TIME: 0.001982 BYTES_RECEIVED: 388 BYTES_SENT: 2327 BINLOG_BYTES_WRITTEN: 0 ROWS_READ: 0 ROWS_SENT: 12 ROWS_DELETED: 0 ROWS_INSERTED: 13 ROWS_UPDATED: 0 SELECT_COMMANDS: 4 UPDATE_COMMANDS: 0 OTHER_COMMANDS: 3 COMMIT_TRANSACTIONS: 0 ROLLBACK_TRANSACTIONS: 0 DENIED_CONNECTIONS: 0 LOST_CONNECTIONS: 0 ACCESS_DENIED: 0 EMPTY_QUERIES: 1 SELECT * FROM INFORMATION_SCHEMA.CLIENT_STATISTICS\G *************************** 1. row *************************** CLIENT: localhost TOTAL_CONNECTIONS: 3 CONCURRENT_CONNECTIONS: 0 CONNECTED_TIME: 4883 BUSY_TIME: 0.009722 CPU_TIME: 0.0102131 BYTES_RECEIVED: 841 BYTES_SENT: 13897 BINLOG_BYTES_WRITTEN: 0 ROWS_READ: 0 ROWS_SENT: 214 ROWS_DELETED: 0 ROWS_INSERTED: 207 ROWS_UPDATED: 0 SELECT_COMMANDS: 10 UPDATE_COMMANDS: 0 OTHER_COMMANDS: 13 COMMIT_TRANSACTIONS: 0 ROLLBACK_TRANSACTIONS: 0 DENIED_CONNECTIONS: 0 LOST_CONNECTIONS: 0 ACCESS_DENIED: 0 EMPTY_QUERIES: 1 1 row in set (0.00 sec) SELECT * FROM INFORMATION_SCHEMA.INDEX_STATISTICS WHERE TABLE_NAME = "author"; +--------------+------------+------------+-----------+ | TABLE_SCHEMA | TABLE_NAME | INDEX_NAME | ROWS_READ | +--------------+------------+------------+-----------+ | books | author | by_name | 15 | +--------------+------------+------------+-----------+ SELECT * FROM INFORMATION_SCHEMA.TABLE_STATISTICS WHERE TABLE_NAME='user'; +--------------+------------+-----------+--------------+------------------------+ | TABLE_SCHEMA | TABLE_NAME | ROWS_READ | ROWS_CHANGED | ROWS_CHANGED_X_INDEXES | +--------------+------------+-----------+--------------+------------------------+ | mysql | user | 5 | 2 | 2 | +--------------+------------+-----------+--------------+------------------------+ Using the SHOW StatementsAs an alternative to the INFORMATION_SCHEMA tables, the userstat plugin also adds the SHOW USER_STATISTICS, the SHOW CLIENT_STATISTICS, the SHOW INDEX_STATISTICS, and the SHOW TABLE_STATISTICS statements. These commands are another way to display the information stored in the information schema tables. WHERE clauses are accepted. LIKE clauses are accepted but ignored. SHOW USER_STATISTICS SHOW CLIENT_STATISTICS SHOW INDEX_STATISTICS SHOW TABLE_STATISTICS Flushing Plugin DataThe userstat plugin also adds the FLUSH USER_STATISTICS, FLUSH CLIENT_STATISTICS, FLUSH INDEX_STATISTICS, and FLUSH TABLE_STATISTICS statements, which discard the information stored in the specified information schema table. FLUSH USER_STATISTICS FLUSH CLIENT_STATISTICS FLUSH INDEX_STATISTICS FLUSH TABLE_STATISTICS Versions USER_STATISTICS VersionStatusIntroduced 2.0StableMariaDB 10.1.18 2.0GammaMariaDB 10.1.1 CLIENT_STATISTICS VersionStatusIntroduced 2.0StableMariaDB 10.1.13 2.0GammaMariaDB 10.1.1 INDEX_STATISTICS VersionStatusIntroduced 2.0StableMariaDB 10.1.13 2.0GammaMariaDB 10.1.1 TABLE_STATISTICS VersionStatusIntroduced 2.0StableMariaDB 10.1.18 2.0GammaMariaDB 10.1.1 System Variables userstat Description: If set to 1, user statistics will be activated. Commandline: --userstat=1 Scope: Global Dynamic: Yes Data Type: boolean Default Value: OFF |
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