Search Results
https://dev.mysql.com/doc/internals/en/store-lock.html
Synopsis virtual THR_LOCK_DATA ** store_lock ( thd, to, lock_type); THD * thd ; THR_LOCK_DATA ** to ; enum thr_lock_type lock_type ; Description This is the store_lock method. The idea with handler::store_lock() is the following: The statement ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-ndbinfo-cluster-locks.html
The cluster_locks table provides information about current lock requests holding and waiting for locks on NDB tables in an NDB Cluster, and is intended as a companion table to cluster_operations. Information obtain from the cluster_locks table may ...Its value is always one of H (holding) or W ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-ndbinfo-server-locks.html
The server_locks table is similar in structure to the cluster_locks table, and provides a subset of the information found in the latter table, but which is specific to the SQL node (MySQL server) where it resides. (The cluster_locks table provides ...The tableid is assigned to the table by NDB; the same ID is used for this table in other ndbinfo tables, as well as in the output of ...
https://dev.mysql.com/doc/internals/en/implementing-store-lock-method.html
The [custom-engine.html#custom-engine-api-reference-store_lock store_lock()] method is called before any reading or writing is performed. Before adding the lock into the table lock handler mysqld calls store lock with the requested locks. Store ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-standard-monitor.html
The Lock Monitor is the same as the Standard Monitor except that it includes additional lock information. Enabling either monitor for periodic output turns on the same output stream, but the stream includes extra information if the Lock Monitor is ...Standard Monitor output is limited to 1MB when produced using the SHOW ENGINE INNODB STATUS ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-table-wait-summary-tables.html
The following sections describe the table I/O and lock wait summary tables: table_io_waits_summary_by_index_usage: Table I/O waits per index table_io_waits_summary_by_table: Table I/O waits per table table_lock_waits_summary_by_table: Table lock ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-next-key-locking.html
If the locks set on the index records in the scanned range do not lock out inserts made in the gaps (in this case, the gap between 90 and 102), another session can insert a new row into the table with an id of 101. To prevent phantoms, InnoDB uses ... The so-called phantom problem occurs within a transaction when the same query produces different sets of rows at different ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-data-lock-waits-table.html
The data_lock_waits table implements a many-to-many relationship showing which data lock requests in the data_locks table are blocked by which held data locks in the data_locks table. Held locks in data_locks appear in data_lock_waits only if they ...The Performance Schema collects information that is already available in the server, so there is no memory or CPU overhead to generate this information or need for parameters that control its ...
https://dev.mysql.com/doc/mysql-errors/8.4/en/server-error-reference.html
You can increase the value of the innodb_lock_wait_timeout configuration option if SQL statements should wait longer for other transactions to complete, or decrease it if too many long-running transactions are causing locking problems and reducing ... The MySQL server writes some error messages to its error log, and sends others to client ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-information-schema-transactions.html
Each transaction in InnoDB that is waiting for another transaction to release a lock (INNODB_TRX.TRX_STATE is LOCK WAIT) is blocked by exactly one blocking lock request. That blocking lock request is for a row or table lock held by another ...