MySQL slots under PHP / PDO

Question

I'm evaluating a migration to pdo on some hosts (VPS) but it seems to come at a price of more memory required.

Q: in php.ini, there's a setting:

pdo_mysql.cache_size = 2000

I can't find much information about it, it refers to mysql-slots, whats the purpose and maths behind? After all, the mysqld has a cache of it's own - why should pdo have one too?

regards,

//t

Answer 1

This setting and feature were removed (see related diff) due to a bug.