Hi! >This is a followup to my previous messages indicating database slow down. >After noticing the queries start to slow down earlier i decided to try and >get some debug info. a show table status had one interesting thing. > >| raw | InnoDB | Fixed | 169681 | 1030 | >174817280 |
Sorry this is a known bug in SHOW TABLE STATUS in InnoDB. It estimates the row count too big if you have big BLOBs in your table. >the 4th column being interesting. It seems to "think" there are 169,681 rows >but this isn't true. The query operates on about 2000 rows each time then >deletes and commits them so why does it think there are 170K rows? Could >this be a source of the problem. Any suggestions welcome. No, the estimate has no effect on TRUNCATE TABLE. But if you are running MySQL-3.23, then TRUNCATE TABLE actually internally is DELETE FROM... and it should not run any faster than DELETE FROM... If you need quick emptying in 3.23, use DROP TABLE + CREATE TABLE. >There is no particular query which causes this to happen because the same >batch of queries are happening over and over and over again. So What could >be wrong. It takes about 2 minutes to do a shutdown when its gets like this >and either way I can't afford to restart the database once its implemented. > >As a note, a restart of the database sets the row count of raw to 0 so I >really think it is related to this. Most of the queries revolve around this >table so any problems with it are going to cause me big problems. > >Any help much appreciated. >Richard Regards, Heikki --------------------------------------------------------------------- Before posting, please check: http://www.mysql.com/manual.php (the manual) http://lists.mysql.com/ (the list archive) To request this thread, e-mail <[EMAIL PROTECTED]> To unsubscribe, e-mail <[EMAIL PROTECTED]> Trouble unsubscribing? Try: http://lists.mysql.com/php/unsubscribe.php
