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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. When you issue a consistent read (that is, an ordinary SELECT statement), InnoDB gives your transaction a timepoint ...If ...The query sees the changes made by transactions that committed before that point in time, and no changes made by later or uncommitted ...
https://dev.mysql.com/doc/refman/8.4/en/index-statistics.html
For InnoDB and MyISAM tables, you have some control over collection of table statistics by means of the innodb_stats_method and myisam_stats_method system variables, respectively. The innodb_stats_method system variable has a global value; the ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-online-ddl-single-multi.html
Before the introduction of online DDL, it was common practice to combine many DDL operations into a single ALTER TABLE statement. Because each ALTER TABLE statement involved copying and rebuilding the table, it was more efficient to make several ...
https://dev.mysql.com/doc/mysql-em-plugin/en/myoem-config-metric-innodbmemcachedconfiguration-category.html
Lists the InnoDB Memcached Configuration configuration metrics and provides a brief description of each. Table 7.16 InnoDB Memcached Configuration Configuration Metrics NameDescriptionBk Commit Interval Specifies how often to auto-commit idle ...
https://dev.mysql.com/doc/mysql-em-plugin/en/myoem-cluster-config-metric-clusterstatus-category.html
Table 9.1 InnoDB Cluster Status Configuration Metrics NameDescriptionCluster ID The ID of the MySQL InnoDB Cluster. Lists the Cluster Status configuration metrics and provides a brief description of each. Ssl Enabled True if mysqld supports SSL ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-adaptive-hash.html
The adaptive hash index enables InnoDB to perform more like an in-memory database on systems with appropriate combinations of workload and sufficient memory for the buffer pool without sacrificing transactional features or reliability. The adaptive ...Based on the observed pattern of searches, a hash index is built using a prefix of the index ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-statistics-estimation.html
Running SHOW TABLE STATUS, SHOW INDEX, or querying the Information Schema TABLES or STATISTICS tables with the innodb_stats_on_metadata option enabled. Optimizer statistics are persisted to disk by default, enabled by the innodb_stats_persistent ...
https://dev.mysql.com/doc/mysql-em-plugin/en/myoem-clusterset-config-metric-clusterstatus-category.html
Lists the InnoDB ClusterSet Status configuration metrics and provides a brief description of each. Table 11.1 InnoDB ClusterSet Status Configuration Metrics NameDescriptionClusterSet ID The ID of the MySQL InnoDB ClusterSet.
https://dev.mysql.com/doc/refman/8.4/en/innodb-information-schema-innodb_cmpmem.html
The INNODB_CMPMEM and INNODB_CMPMEM_RESET tables provide status information about compressed pages that reside in the buffer pool. Please consult Section 17.9, “InnoDB Table and Page Compression” for further information on compressed tables and ...Internal Details InnoDB uses a buddy allocator system to manage memory allocated to pages of various sizes, from 1KB to ...
https://dev.mysql.com/doc/mysql-em-plugin/en/myoem-metric-sysschema-innodbrowlockwaiters-category.html
Lists the Sys Schema InnoDB Row Lock Waits metrics and provides a brief description of each.