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https://dev.mysql.com/doc/refman/8.4/en/innodb-performance-compression-oltp.html
Traditionally, the InnoDB compression feature was recommended primarily for read-only or read-mostly workloads, such as in a data warehouse configuration. If you are certain that the zlib version is not subject to change, disable ...These ...The ...
https://dev.mysql.com/doc/internals/en/innodb-infimum-and-supremum-records.html
InnoDB sets up an infimum record and a supremum record automatically in the root page when an index is first created, and never deletes them. The InnoDB code comments distinguish between “the infimum and supremum records” and the “user ...
https://dev.mysql.com/doc/refman/8.4/en/information-schema-innodb-cmp-per-index-table.html
The INNODB_CMP_PER_INDEX and INNODB_CMP_PER_INDEX_RESET tables provide status information on operations related to compressed InnoDB tables and indexes, with separate statistics for each combination of database, table, and index, to help you ...In ...Pages are compressed whenever an empty page is created or the space for the uncompressed modification log runs ...
https://dev.mysql.com/doc/internals/en/innodb-overview.html
The chart below shows the three parts of a physical record. Name Size Field Start Offsets (F*1) or (F*2) bytes Extra Bytes 6 bytes Field Contents depends on content Legend: The letter 'F' stands for 'Number Of Fields'. The meaning of the parts is ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-performance-midpoint_insertion.html
Rather than using a strict LRU algorithm, InnoDB uses a technique to minimize the amount of data that is brought into the buffer pool and never accessed again. Both innodb_old_blocks_pct and innodb_old_blocks_time can be specified in the MySQL ...
https://dev.mysql.com/doc/refman/8.4/en/information-schema-innodb-tablestats-table.html
This data is used by the MySQL optimizer to calculate which index to use when querying an InnoDB table. CLUST_INDEX_SIZE The number of pages on disk that store the clustered index, which holds the InnoDB table data in primary key order. The ...
https://dev.mysql.com/doc/internals/en/innodb-user-records.html
But by definition the records of a B-tree must be accessible in order by key value, so there is a record pointer in each record (the "next" field in the Extra Bytes) which points to the next record in key order. In the User Records part of a page, ...
https://dev.mysql.com/doc/refman/8.4/en/information-schema-innodb-trx-table.html
When this column and TRX_IS_READ_ONLY are both 1, InnoDB optimizes the transaction to reduce the overhead associated with transactions that change table data. The INNODB_TRX table provides information about every transaction currently executing ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-tablespace-autoextend-size.html
By default, when a file-per-table or general tablespace requires additional space, the tablespace is extended incrementally according to the following rules: If the tablespace is less than an extent in size, it is extended one page at a time. The ...If the tablespace is greater than 1 extent but smaller than 32 extents in size, it is extended one extent at a ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-disabling-tablespace-path-validation.html
At startup, InnoDB scans directories defined by the innodb_directories variable for tablespace files. The paths of discovered tablespace files are validated against the paths recorded in the data dictionary. If log_error_verbosity is set to 3, the ...If the paths do not match, the paths in the data dictionary are ...This ...