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https://dev.mysql.com/doc/refman/8.4/en/innodb-deadlocks-handling.html
When modifying multiple tables within a transaction, or different sets of rows in the same table, do those operations in a consistent order each time. This section builds on the conceptual information about deadlocks in Section 17.7.5.2, ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-information-schema-examples.html
SELECT THREAD_ID, SQL_TEXT FROM performance_schema.events_statements_history WHERE THREAD_ID = 28 ORDER BY EVENT_ID; Correlating InnoDB Transactions with MySQL Sessions Sometimes it is useful to correlate internal InnoDB locking information with the ... This section describes the use of locking information as exposed by the Performance Schema data_locks and data_lock_waits ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-information-schema-files-table.html
The Information Schema FILES table provides metadata about all InnoDB tablespace types including file-per-table tablespaces, general tablespaces, the system tablespace, temporary table tablespaces, and undo tablespaces (if present). For more ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-information-schema-metrics-table.html
The INNODB_METRICS table provides information about InnoDB performance and resource-related counters. SET GLOBAL innodb_monitor_disable = [counter-name|module_name|pattern|all]; innodb_monitor_reset: Resets counter values to zero. SET GLOBAL ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-information-schema-system-tables.html
You can extract metadata about schema objects managed by InnoDB using InnoDB INFORMATION_SCHEMA tables. Traditionally, you would get this type of information using the techniques from Section 17.17, “InnoDB Monitors”, setting up InnoDB monitors ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-multi-versioning.html
This removal operation is called a purge, and it is quite fast, usually taking the same order of time as the SQL statement that did the deletion. It keeps information about old versions of changed rows to support transactional features such as ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-next-key-locking.html
If one session has a shared or exclusive lock on record R in an index, another session cannot insert a new index record in the gap immediately before R in the index order. The so-called phantom problem occurs within a transaction when the same ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-online-ddl-limitations.html
Secondary indexes are not created as efficiently because keys are inserted in the order they appeared in the primary key. The following limitations apply to online DDL operations: The table is copied when creating an index on a TEMPORARY TABLE. The ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-online-ddl-performance.html
LOCK clauses are described below, in order of least to most restrictive: LOCK=NONE: Permits concurrent queries and DML. Online DDL improves several aspects of MySQL operation: Applications that access the table are more responsive because queries ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-performance-read_ahead.html
Random read-ahead is a technique that predicts when pages might be needed soon based on pages already in the buffer pool, regardless of the order in which those pages were read. A read-ahead request is an I/O request to prefetch multiple pages in ...