Emergency

Search Results for: innodb myisam large table

Performance problem with Innodb and DROP TABLE

I’ve been working with an application which does a lot of CREATE and DROP table for Innodb tables and we’ve discovered DROP TABLE can take a lot of time and when it happens a lot …


Moving from MyISAM to Innodb or XtraDB. Basics

I do not know if it is because we’re hosting a free webinar on migrating MyISAM to Innodb or some other reason but recently I see a lot of questions about migration from MyISAM to …


How innodb_open_files affects performance

Recently I looked at table_cache sizing which showed larger table cache does not always provides the best performance. So I decided to look at yet another similar variable – innodb_open_files which defines how many files …


table_cache negative scalability

Couple of months ago there was a post by FreshBooks on getting great performance improvements by lowering table_cache variable. So I decided to investigate what is really happening here. The “common sense” approach to tuning …


Innodb performance gotcha w Larger queries.

Couple of days ago I was looking for a way to improve update performance for the application and I was replacing single value UPDATE with multiple value REPLACE (though I also saw the same problem …


The perils of InnoDB with Debian and startup scripts

Are you running MySQL on Debian or Ubuntu with InnoDB? You might want to disable /etc/mysql/debian-start. When you run /etc/init.d/mysql start it runs this script, which runs mysqlcheck, which can destroy performance. It can happen …


Should you move from MyISAM to Innodb ?

There is significant portion of customers which are still using MyISAM when they come to us, so one of the big questions is when it is feasible to move to Innodb and when staying on …


How much space does empty Innodb table take ?

How much space would empty MyISAM table take ? Probably 8K for .frm file, 1KB for .MYI file and 0 for MYD file. .MYI file can be larger if you have many indexes. How much …


Thoughs on Innodb Incremental Backups

For normal Innodb “hot” backups we use LVM or other snapshot based technologies with pretty good success. However having incremental backups remain the problem. First why do you need incremental backups at all ? Why …


ANALYZE: MyISAM vs Innodb

Following up on my Previous Post I decided to do little test to see how accurate stats we can get for for Index Stats created by ANALYZE TABLE for MyISAM and Innodb. But before we …