Many backup tools including Percona Xtrabackup, MyLVMBackup and others use FLUSH TABLES WITH READ LOCK to temporary make MySQL read only. In many cases the period for which server has to be made read only is very short, just few seconds, yet the impact of FLUSH TABLES WITH READ LOCK can be quite large because [...]
Many people use mysqldump –single-transaction to get consistent backup for their Innodb tables without making database read only. In most cases it works, but did you know there are some cases when you can get table entirely missing from the backup if you use this technique ? The problem comes from the fact how MySQL’s [...]
One common theme in the questions our MySQL Support customers ask is MySQL Replication Lag. The story is typically along the lines everything is same as before and for some unknown reason the slave is started to lag and not catching up any more. I always smile at “nothing has changed” claim as it usually [...]
We’ve had such a large number of signups to our Migrating MyISAM to InnoDB webinar, that we decided to hold one more before the year is out: December, 8th 9AM PST: Introduction to Percona Server, XtraDB and Xtrabackup.
I have a 5G mysqldump which takes 30 minutes to restore from backup.Â That means that when the database reaches 50G, it should take 30×10=5 hours to restore.Â Right?Â Wrong.
First time I heard about Galera on Percona Performance Conference 2009, Seppo Jaakola was presenting “Galera: Multi-Master Synchronous MySQL Replication Clusters”. It was impressed as I personally always wanted it for InnoDB, but we had it in plans at the bottom of the list, as this is very hard to implement properly. The idea by [...]
During preparation of Percona-XtraDB template to run in RightScale environment, I noticed that IO performance on EBS volume in EC2 cloud is not quite perfect. So I have spent some time benchmarking volumes. Interesting part with EBS volumes is that you see it as device in your OS, so you can easily make software RAID [...]
Speed of InnoDB recovery is known and quite annoying problem. It was discussed many times, see: http://bugs.mysql.com/bug.php?id=29847 http://dammit.lt/2008/10/26/innodb-crash-recovery/ This is problem when your InnoDB crashes, it may takes long time to start. Also it affects restoring from backup (both LVM and xtrabackup / innobackup) In this is simple test, I do crash mysql during in-memory [...]
For long time as main backup solution for MySQL on Linux we have been using LVM snapshots. Performance concerns from performance critical envinronment caused us to do LVM performance research which showed horrible results forcing us to look at more performing alternatives. Innodb Hot Backup is a good working solution but it is not Open [...]