https://dev.mysql.com/locking-service-udf-interface.html
The final argument is an integer timeout indicating how many seconds to wait to acquire the locks before giving up. Timeout values must be integers indicating how many seconds to wait to acquire locks before giving up with an error. If the timeout ... This section describes how to use the locking service user-defined function (UDF) ...
https://dev.mysql.com/midpoint-insertion.html
If the block stays at the beginning of the sublist for a long enough time, it is demoted to the warm sublist. This time is determined by the value of the key_cache_age_threshold component of the key cache. By default, the key cache management ...
https://dev.mysql.com/mutex-instances-table.html
A mutex is a synchronization mechanism used in the code to enforce that only one thread at a given time can have access to some common resource. The work performed while holding a mutex is said to be in a “critical section,” and multiple queries ... The mutex_instances table lists all the mutexes seen by the Performance Schema while the server ...
https://dev.mysql.com/myisam-crash-recovery.html
If you run myisamchk to check tables that mysqld is updating at the same time, you may get a warning that a table is corrupt even when it is not. If the server is run with external locking enabled, you can use myisamchk to check tables at any time.
https://dev.mysql.com/myisam-maintenance-schedule.html
If you are performing many updates to MyISAM tables with dynamic-sized rows (tables with VARCHAR, BLOB, or TEXT columns) or have tables with many deleted rows you may want to defragment/reclaim space from the tables from time to time. It is a good ...
https://dev.mysql.com/myisam-table-close.html
The counter works as follows: The first time a table is updated in MySQL, a counter in the header of the index files is incremented. (The table may still be okay because MySQL always issues writes for everything between each statement.) A table was ... Each MyISAM index file (.MYI file) has a counter in the header that can be used to check whether a table has been closed ...
https://dev.mysql.com/myisamchk-general-options.html
You can set both variables to large values, because only one of them is used at a time. The options described in this section can be used for any type of table maintenance operation performed by myisamchk. The sections following this one describe ...
https://dev.mysql.com/mysql-cluster-backup-concepts.html
A backup is a snapshot of the database at a given time. The data actually stored in the database tables at the time that the backup was made Transaction log. A sequential record telling how and when data was stored in the database Each of these ...
https://dev.mysql.com/mysql-cluster-basics.html
There are as many data nodes as there are replicas, times the number of fragments (see Section 22.1.2, “NDB Cluster Nodes, Node Groups, Replicas, and Partitions”). More specific to NDB Cluster, a checkpoint is a point in time where all committed ... NDBCLUSTER (also known as NDB) is an in-memory storage engine offering high-availability and data-persistence ...
https://dev.mysql.com/mysql-cluster-ndb-innodb-engines.html
The NDB storage engine is implemented using a distributed, shared-nothing architecture, which causes it to behave differently from InnoDB in a number of ways. For those unaccustomed to working with NDB, unexpected behaviors can arise due to its ...
