MySQL Forums
Forum List  »  MyISAM

Server completely locked up on ALTER TABLE statement
Posted by: Beat Vontobel
Date: April 10, 2006 07:17AM

Hi everybody,

Maybe somebody has a hint on this (is it a known bug?):

I do an ALTER TABLE on a reasonably big MyISAM table (32 million rows, 2.5 GB). The statement takes about 40 minutes to execute, which in itself is okay.

But during the last few minutes the state of the ALTER TABLE query (as displayed in the output of SHOW PROCESSLIST) changes to "copy to tmp table" and the server (5.0.19) starts to block all other queries (!) in state "Opening tables". This affects even queries that don't use the table affected by the ALTER statement, and not even the same schema!

This effectively takes down the server as (with 200 queries per second) after about a minute we reach maximum connection limits for different users, hosts and eventually the whole server.

Does anybody know what's going on here?

Thanks,
Beat

Beat Vontobel
http://www.futhark.ch/mysql

Options: ReplyQuote




Sorry, you can't reply to this topic. It has been closed.

Content reproduced on this site is the property of the respective copyright holders. It is not reviewed in advance by Oracle and does not necessarily represent the opinion of Oracle or any other party.