Mysql Error 1615 Workaround _mysql

There was a very strange problem when we tested the compliance script today. MySQL Report error:

ERROR 1615 (HY000): Prepared statement needs to be re-prepared

After testing, it was found that the problem was not a compliance script. After a search. found that the original MySQL variable value set unreasonable cause, adjust the following values:

Table_open_cache 64=>16384
Table_definition_cache 256=>16384
mysql> set global table_open_cache=16384;

mysql> set global table_definition_cache=16384;

Go back to the script, all OK. Finally found that the DB machine too many databases, it is estimated that the open table too much caused by the lock table.