If you have configured non-persistent optimizer statistics (a non-default configuration)
InnoDBcomputes index cardinality values for a table the first time that table is accessed after startup, instead of storing such values in the table. This step can take significant time on systems that partition the data into many tables. Since this overhead only applies to the initial table open operation, to “warm up” a table for later use, access it immediately after startup by issuing a statement such as
SELECT 1 FROM.
As of MySQL 5.6.6, optimizer statistics are persisted to disk by default, enabled by the
innodb_stats_persistentconfiguration option. For information about persistent optimizer statistics, see Section 18.104.22.168, “Configuring Persistent Optimizer Statistics Parameters”.