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https://dev.mysql.com/doc/refman/8.4/en/information-schema-ndb-transid-mysql-connection-map-table.html
For this table to be created, the MySQL Server must be a binary supplied with the NDB Cluster distribution, or one built from the NDB Cluster sources with NDB storage engine support enabled. The ndb_transid_mysql_connection_map table provides a ...
https://dev.mysql.com/doc/refman/8.4/en/information-schema-tp-thread-state-table.html
For example, if an application uses this query: SELECT * FROM INFORMATION_SCHEMA.TP_THREAD_STATE; The application should use this query instead: SELECT * FROM performance_schema.tp_thread_state; The TP_THREAD_STATE table has one row per thread ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-adaptive-hash.html
If there are numerous threads waiting on rw-latches created in btr0sea.c, consider increasing the number of adaptive hash index partitions or disabling the adaptive hash index. The adaptive hash index enables InnoDB to perform more like an ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-benefits.html
You can create and drop indexes and perform other DDL operations with much less impact on performance and availability. InnoDB tables have the following benefits: If the server unexpectedly exits because of a hardware or software issue, regardless ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-best-practices.html
Run the server with the --sql_mode=NO_ENGINE_SUBSTITUTION option to prevent tables from being created with storage engines that you do not want to use. Specify a primary key for every table using the most frequently queried column or columns, or an ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-compression.html
Using the compression features of InnoDB, you can create tables where the data is stored in compressed form. This section provides information about the InnoDB table compression and InnoDB page compression features. The page compression feature is ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-consistent-read.html
A consistent read means that InnoDB uses multi-versioning to present to a query a snapshot of the database at a point in time. The query sees the changes made by transactions that committed before that point in time, and no changes made by later or ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-deadlocks-handling.html
Another way to serialize transactions is to create an auxiliary “semaphore” table that contains just a single row. This section builds on the conceptual information about deadlocks in Section 17.7.5.2, “Deadlock Detection”. It explains how ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-disk-io.html
InnoDB uses asynchronous disk I/O where possible, by creating a number of threads to handle I/O operations, while permitting other database operations to proceed while the I/O is still in progress. On Linux and Windows platforms, InnoDB uses the ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-enabling-monitors.html
When this option is used, InnoDB creates a file named innodb_status.pid in the data directory and writes output to it every 15 seconds, approximately. When InnoDB monitors are enabled for periodic output, InnoDB writes the output to mysqld server ...