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https://dev.mysql.com/innodb-online-ddl-performance.html
Use this clause if the primary concern is finishing the DDL operation in the shortest amount of time possible, and concurrent query and DML access is not necessary. In the case of a long running or inactive transaction, an online DDL operation can ... Online DDL improves several aspects of MySQL operation: Applications that access the table are more responsive because queries and DML operations on the table can proceed while the DDL operation is in ...
https://dev.mysql.com/innodb-undo-tablespaces.html
Default undo tablespaces are created at initialization time to provide a location for rollback segments that must exist before SQL statements can be accepted. As of MySQL 8.0.14, additional undo tablespaces can be created at runtime using SQL. As of ... Undo tablespaces contain undo logs, which are collections of undo log records that contain information about how to undo the latest change by a transaction to a clustered index ...
https://dev.mysql.com/memory-summary-tables.html
Allocating a single byte one million times is not the same as allocating one million bytes a single time; tracking both sizes and counts can expose the difference. Memory summary tables do not contain timing information because memory events are not ...Operation counts help to understand or tune the overall pressure the server is putting on the memory allocator, which has an impact on ...
https://dev.mysql.com/myisamchk-table-info.html
Index Whether a key value can exist multiple times in the index. By default this is 1024, but the value may be changed at compile time when MySQL is built from source. To obtain a description of a MyISAM table or statistics about it, use the ...
https://dev.mysql.com/mysql-cluster-api-definition.html
This occurs when a given redo log flush takes longer than RedoOverCommitLimit seconds, more than RedoOverCommitCounter times, causing any pending transactions to be aborted. As long as the API node is not connected to any new data nodes, the value ... The [mysqld] and [api] sections in the config.ini file define the behavior of the MySQL servers (SQL nodes) and other applications (API nodes) used to access cluster ...
https://dev.mysql.com/mysql-cluster-installer-using.html
Real-time: Maximize performance while maximizing sensitivity to timeouts in order to minimize the time needed to detect failed cluster processes. Be aware that it may take some time for information to be retrieved from remote hosts. When this screen ... The NDB Cluster Auto-Installer interface is made up of several pages, each corresponding to a step in the process used to configure and deploy an NDB ...
https://dev.mysql.com/mysql-cluster-programs-ndb-mgmd.html
--config-cache Property Value Command-Line Format --config-cache[=TRUE|FALSE] Type Boolean Default Value TRUE This option, whose default value is 1 (or TRUE, or ON), can be used to disable the management server's configuration cache, so that it ...
https://dev.mysql.com/mysql-commands.html
Sometimes a very wide result set is difficult to read on the screen. Have a tee file enabled and pager set to less, and you are able to browse the results using the less program and still have everything appended into a file the same time. The ...
https://dev.mysql.com/mysqlpump.html
This option is disabled by default because histogram generation for large tables can take a long time. It is useful only with transactional tables such as InnoDB, because then it dumps the consistent state of the database at the time when START ...
https://dev.mysql.com/performance-schema-instrument-filtering.html
The setup_instruments table lists the available instruments: mysql> SELECT NAME, ENABLED, TIMED FROM performance_schema.setup_instruments; +---------------------------------------------------+---------+-------+ | NAME | ENABLED | TIMED | ...| ...
Document created the 26/06/2006, last modified the 26/10/2018
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