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https://dev.mysql.com/innodb-memcached-internals.html
The config_options table stores memcached-related settings that can be changed at runtime using SQL. The expire_time_column value is related to the way memcached hashes requests to different servers and caches data in memory. The maximum expire time ... The InnoDB memcached engine accesses InnoDB through InnoDB APIs, most of which are directly adopted from embedded ...
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-ndbinfo-cpustat-1sec.html
The cpustat-1sec table provides raw, per-thread CPU data obtained each second for each thread running in the NDB kernel. Like cpustat_50ms and cpustat_20sec, this table shows 20 measurement sets per thread, each referencing a period of the named ...
https://dev.mysql.com/mysql-cluster-ndbinfo-cpustat-20sec.html
The cpustat_20sec table provides raw, per-thread CPU data obtained each 20 seconds, for each thread running in the NDB kernel. Like cpustat_50ms and cpustat_1sec, this table shows 20 measurement sets per thread, each referencing a period of the ...
https://dev.mysql.com/mysql-cluster-ndbinfo-cpustat-50ms.html
The cpustat_50ms table provides raw, per-thread CPU data obtained each 50 milliseconds for each thread running in the NDB kernel. Like cpustat_1sec and cpustat_20sec, this table shows 20 measurement sets per thread, each referencing a period of the ...
Document created the 26/06/2006, last modified the 26/10/2018
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