If you're experiencing a high rate of open table cache misses with multiple connections to a database, you can try these steps:

Increase the table_open_cache value If the number of opened tables is increasing rapidly, you can try increasing the table_open_cache value. Make sure your operating system can handle the number of open file descriptors required by the table_open_cache setting.

Check for unused tables If the cache contains more than table_open_cache entries and a table in the cache is no longer being used by any threads, MySQL will close and remove it from the table cache.

Check for table-flushing operations If a table-flushing operation occurs, MySQL will close and remove unused tables from the table cache. This happens when someone issues a FLUSH TABLES statement or executes a mysqladmin flush-tables or mysqladmin refresh command.