It's nothing to do with Saddam Hussein. I know that much.jtaylor wrote:Well, I spotted an issue with the phpbb_sessions table this evening.
It had 55Meg of "overhead".
Tried an overhead, tried a repair - mysqladmin wouldn't let me do it, "The handler for the table doesn't support optimize" and same message for repair.
Copied the table, renamed old one, and overhead has gone.
Any techies out there know the implications of this??
J
My experience of phpBB is limited, to say the least. But I have Google, a little guesswork, and a deceptive air of authority. This may not be the right answer, but it might give you some ideas.
You're probably using an in-memory table for sessions rather than one stored on disk. That improves performance, but session data is lost when MySQL is restarted. Depending on how your hosting provider does accounting, it may also prevent session data from counting against your storage allowance.
Session data is information about who's logged in at any one time. If it's lost, it just means that people have to log in again. Since people can log in and out many times a day, it changes a lot more often than the rest of the database, but doesn't need to be preserved long-term.
As you've discovered, you can't optimize a table that's stored in memory. I expect the idea is you don't need to. It's possible you've found a bug in MySQL.
Restart the MySQL server, drop and recreate the table, or upgrade MySQL.
It might be the reported memory use is wrong, though, and this 'overhead' is a phantom. See, for example, bug #18610. If that's the problem, you needn't do anything, unless you care about accurate statistics.