MySQL Forums
Forum List  »  Performance

tables_cache and open_files Server settings
Posted by: Erin ONeill
Date: June 30, 2005 11:38AM

I'm trying to tweak a MySQL server to get blazing performance out of it. I've been reading books and online. I think I have a handle on some of the formulas for determining values. Now I need more information about two settings and I can't seem to find the info (perhaps my cold has frozen my brain?).

It's my understanding that the tables cache setting is this formula:
max_connections * avg.-num-tables-in-join <= open_files

open_files is 3010. max_connections is 400, table joins tend to be 3-4 tables. So 3*400 = 1200, which is lower than 3010. I set my server to this parameter and the server screamed. I went on to slow queries. Then the server crashed with the error: too many open files!!

Why didn't MySQL close files after the 3010 limit was reached? Why did it crash, rather than close files.

If the formula I have is wrong -- does anyone have a more correct one?

I do know that cache tables really speeds up the server - I just can't have it crashing and want to prevent that.

thanks all
erin

Options: ReplyQuote


Subject
Views
Written By
Posted
tables_cache and open_files Server settings
2667
June 30, 2005 11:38AM


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.