MySQL Forums
Forum List  »  Performance

Re: Server just hanging (Copying to tmp table)
Posted by: Thomas Deliduka
Date: August 29, 2005 08:53PM

Thank you Daniel. You are shedding more light on this. I can see that the tweaking hasn't really done much since I had to reboot over the weekend and today. Well, over the weekend so I could get back to painting I simply rebooted but normally I can issue "FLUSH TABLES" and the problem will go away.

I'm sure 100% key hit rate is a good thing, however, what I notice is that during the problem the hit rate is continuously at 100%, it never falls down. Whereas in normal operations it jumps up and down as queries come in.

Here is the image I had on page one, this demonstrates in a short space how before "FLUSH TABLES" the key hit rate was 100% and then afterwards it hops up and down in normal operation.

Perhaps it's simply showing what is going on and not anything that can help fix it, that a query is stuck somehow and so it's stuck at 100% hit rate until that query is released.

Here is how i know the server is having problems: I have a script I saw an example of in the user notes of the "Kill" command. Basically I run a script that looks at queries that have been running over 600 seconds and it kills them. I will get, for example today, about e-mails reporting on the queries that were killed. Every 5 minutes so I know that every five minutes queries are stuck and I need to go in and flush tables.

Now, perhaps, instead of me going in and flushing tables, perhaps I should retool the script simply to flush tables for me. That way the server may just continue running, eh? If that's the work-around I need then I will do it, I simply was hoping that I wouldn't need to do that and actually find out what is wrong.

I know enough to be dangerous. Thanks for being patient!

Options: ReplyQuote

Written By
Re: Server just hanging (Copying to tmp table)
August 29, 2005 08:53PM
December 07, 2006 10:30AM
September 23, 2005 01:56AM
October 05, 2005 04:58AM
October 05, 2005 11:49PM
October 06, 2005 01:34AM
October 06, 2005 04:57PM
January 21, 2008 10:14AM
January 21, 2008 10:53AM
May 19, 2008 09:41AM
February 05, 2008 10:27AM
March 12, 2008 08:37AM
November 14, 2008 12:31AM

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.